Speaking of "American culture" tends to bring to mind Gandhi's famous line about Western civilization ("It would be a good idea"), but some good evidence in its favor can be found in the throngs of Tribeca Film Festival attendees lining up to see some of the festival's thoughtful documentaries.

Two of the more interesting ones are Chevolution and Waiting for Hockney. Each is devoted to circling around themes that remain fascinatingly (some would say frustratingly) elusive.

They share more than their somewhat challenging subject matter; each probably couldn't have been made without an infusion of capital from fortunes made on the Web.

Julie Checkoway, director of the smaller-scale Waiting, was fortunate in that her brother Neal is a retired Web pioneer. He made his walk-away money by founding the Travelocity travel website in 1996 — just the right moment to command a goodly share of the influx of growingly internet-savvy travelers.

He sold his stake, did a year in the Peace Corps in Jordan with his wife, crafted another start-up with his son, and then headed for Mexico — until his ad hoc turn to producing movies, which became a five-year odyssey.

Chevolution's makers were similarly lucky to draw the interest of Netflix's feature film division, Red Envelope Entertainment. Netflix, of course, has minted money with its (also canny and well-timed) bet that Web surfers would come in droves to rent (and now stream) their movies online.

You couldn't call these high-minded ventures wholly philanthropic. Neal Checkoway describes his sister's project in its early stages as "a prototype", and he used a kind of start-up business model to ushr in finacial partners (like the iDeal Film Fund) along the way.) And Red Envelope head Liesl Copland is an indie-savvy film industry vet who underwrote Chevolution based on her company's vision of how their subscribers interact with the Netflix site.

Even with their relatively trim budgets, these are not slam-dunk films in a tricky art-house market.

Another shared attribute for the two docs is that neither Chevolution co-director Trisha Ziff, whose experience was in galleries and museums, nor Julie Checkoway, who was a sometime professor and a contributor to National Public Radio, quite dared to think they had films to direct--until the were goaded into the medium.

In Checkoway's case, it was Neal who told her she should expand her ambitions for the story she couldn't quite grapple with on radio after amassing 30 hours of audio tape with obsessive, Maryland-based artist/bartender Billy Pappas.

In Ziff's case, it was veteran producer Ron Yerxa, who with partner Albert Berger has launched such offbeat hits as Election and Little Miss Sunshine through their Bona Fide company.

As Checkoway told IFC.com's Stephen Saito: "I was in denial, and my older brother ... said to me, `You know, you really need to think seriously about whether you could make a film of this because I'm telling you, it's a film.'"

Though offering much credit to Gerlaynn Dreyfous, herself an experienced producer (2004's Born Into Brothels) who came along and helped finance and guide the picture through a post-production phase that was just as arduous as he shooting, Neal recalls how rudimentary, if hardly naive, the early going was:

"Certainly when she started she tapped friends and relatives through the pre-production and filming phase. Certainly I have some skin in the game, but I can also say it was more a labor of love and sweat equity on my part. We realized we had the potential for creating the product, and that's how I perceived the process-- let's shape this product into something that would be marketable and can be positioned and packaged and distributed."

It all seems to make sense now, with Waiting standing tall as one of the few Tribeca films to draw distribution money thus far — not surprisingly, from the BBC's Channel 4, for airing in a nation where Hockney, who's securely offstage for the entire film, is a household name.

The courting of Hockney — he ultimately, after seeing the film, signed off on the project's use of his paintings — occurred simultaneously with the quest by Pappas to show Hockney his hyper-realistic pencil drawing of Marilyn Monroe.

(An icon in her own right of course, and by some fuzzy logic involving Castro and J.F.K. she is just a couple degrees of separation from Che, who outlived her by five years to die in Bolivia in October 1967.)

It would be a spoiler to detail how the Pappas-Hockney meeting finally went. It was photographed but not filmed, and later interpreted in widely varying ways.

Suffice to say that the film's emotional resolution is open to interpretation, despite an entirely too on-the-nose song called "Driftwood" that plays annoyingly under the footage.

When Pappas first saw the film, he felt like he'd "been kicked in the chest by a horse." He retreated to Maryland, where he'd continued drawing (the film displays a nude self-portrait of Billy hanging out, Forgetting Sarah Marshall-style) but had returned to his night job of bartending.

By the film's premiere night in downtown New York (which would include a gallery unveiling of Billy's Marilyn and a reunion of filmmakers with subject), Neal was telling himself, "It can only be fascinating."

Happily, Billy was by then reconciled to his filmic portrait and the Checkoways breathed easier: Says Neal, who along with his sister, can stake an honest clam to sharing Billy's working-class roots, having grown up in Newburyport, Massachusetts, as the offspring of an auto mechanic who finally ascended to run a VW dealership:

You could look at my professional or personal life, and my sister's work — we come from humble roots. Part of the reason this story resonated so much with us was here was a working class guy trying to rise above the limits of his particular class, if you will, with no Rolodex and no qualifications other than an art school degree. Billy's mantra was, `Nothing works like work', and to be honest that's how I feel in my professional life.

The Checkoways' documentary, having had a nice reception at Tribeca, now begins making further festival rounds, and although Julie recently took a post as an arts writer (currently blogging re her directorial adventure) at the Salt Lake Tribune, may find herself a fully credentialed documentarian with some career choices to make.

Trisha Ziff, whose film was mentioned early on by that underappreciated cineaste Liz Smith as a contender for next year's documentary Oscar, has her own momentum (as does Luis Lopez, brought in by Yerxa and Copland as an editor but so crucial to the shaping of the film that Ziff happily gave him a directing co-credit).

Although Yerxa insists on downgrading his company's role to a minuscule percentage of the film's heavy lifting, he deserves credit for aligning the project with Copland. The Red Envelope exec not only funded the project, but, Yerxa says, "really got her hands dirty" in the crucial editing phase. He and Berger intend to stick with "the social comedies", like this summer's release of the Sundance discovery Hamlet 2, that make up 90 percent of their slate--but couldn't resist the Che saga: "You do have the opportunity to see Che as a flawed man, but I think it's extraordinary when people put their life on the line."

Although it was the last film Red Envelope greenlit before changing its business model — it has stopped fully financing new films, but is looking to acquire the rights to completed films — it fit neatly into a Red Envelope picture-picking philosophy that had earlier helped launch 2 Days In Paris and No End In Sight.

"It was sort of a no-brainer for us," says Copland, "It's almost like we're programming for our audience in a way. Especially with a film like this, because it is so balanced but also because it's so culturally rich."

Although some of the talking heads natter on in self-satisfied fashion — and you may want to smack the smug young neo-con college kid in a Che T-shirt that says "This shirt brought to you by capitalism" — the film's real heft comes in the archival material Lopez introduced to show history in the making.

The context for the fateful day in 1960 when the photographer and boulevardier Alberto Korda snapped the iconic picture of Che is especially interesting. A terrorist bombing in Havana harbor, intended to undermine the Castro regime that Che had fought so hard to put into place, had killed dozens people and spurred a massive funeral march and rally.

Che silently stepped to the front of the stage to stand with a mixture of anger, sorrow, hope, and defiance, and was looking across the crowd when Korda snapped two images. Neither ran in the national newspaper he was stringing for, but the image gradually took on its own power and the rest, via Chevolution's intelligent treatment, is fascinating sociological history.

If both these documentaries can find a wide audience — and that remains to be seen, as even a good debut at the much bigger Sundance festival no longer seems to guarantee success — then the culture-minded Neal Checkoway, as well as Red Envelope, will have made a bet with their heart that also happens to pay off.

There is more accessible fare at Tribeca. Playing for Change, for example, is a documentary that finds cause for optimism in its tender-hearted and winning look at how musicians worldwide can keep a musical message volleying around the globe.

But Chevolution and Waiting for Hockney seem to benefit from something more visceral, and it may be that what they share in philosophical underpinning has brought them to marker at precisely the right time.

Quotes elicited by Saito from each director show a fascinating congruency in terms of this moment in the zeitgeist. Said Ziff:

"I think it comes back to another question, which is why do we need heroes? What is it that's so appealing that we're seduced to hear the story again and again in all these different versions, or wear it as a T-shirt or have a poster on our wall? There's something very seductive about [Che], or the fiction of him...and I think it's because we live in a time where people are lost, where there is no leadership, where life isn't about making choices because you believe in them. I think we live in a diminished moment, where there isn't the idealism that existed at the moment where he was strong in the '60's."

As Julie Checkoway sees it, in discussing an American Idol world of instant celebrity:

The thing that bothers me about contemporary culture is this notion that many of us, and the culture in general, walk around thinking, someone is going to save us from our ordinary lives.

I was talking to someone the other day who said he thinks the reason it's that way is that we've lost a sense of what a road map should be for how a life can be lived, so all we have is this trajectory of being invisible and suddenly being incredibly visible and fixed and fine and redeemed.

And so when that happens for Billy, I was really dubious, but I also was really happy for him and at the same time...it would be impossible for me to tell a story that was in some way simplistic about fame.

Thanks to the money that's still flowing from Internet savants who took the proceeds off the table at the right time, neither she nor the makers of Chevolution had to.