Marc Andreessen would rather blog from home in his underwear than give an interview to a journalist, especially in front of an audience. That’s what he wrote in his blog earlier this year. Thankfully, this one time, Andreessen got dressed and stepped onstage.

At 37, Andreessen is a legend in Silicon Valley. He created, with Eric Bina, the first graphical browser while at the University of Illinois, then co-founded Netscape Communications with überentrepreneur Jim Clark in the early 1990s. Netscape’s browser brought the internet to the masses, set off the dotcom boom, and so angered Microsoft at the time that Steve Ballmer, now the software giant’s C.E.O., led employees in “Kill Netscape!” chants. By bundling its Internet Explorer browser into Windows, Microsoft eventually drove Netscape into the arms of a suitor: AOL bought Netscape in 1999 for $4.2 billion.

Andreessen hasn’t had a success of that magnitude since. But he did create another billion-dollar company, Loudcloud, a tech-services outfit that later changed its name to Opsware and was sold to Hewlett-Packard for $1.6 billion. More recently, Andreessen started Ning, a website that lets anyone create a mini social network. Its most prominent customer: 50 Cent.

Andreessen joined Face­book’s board this year, invested in Twitter, and generally manages to show up on the front end of new technology trends. His blog, Blog.pmarca.com, has been a tech-industry must-read, in part because he’s willing to be brutally outspoken. In February, Andreessen ignited emotions when he blogged that he was starting a “New York Times Deathwatch.” ( Watch an exclusive video of Andreessen talking about the future of newspapers.)

Condé Nast Portfolio’s Kevin Maney interviewed Andreessen at a gathering of Silicon Valley’s Churchill Club in Palo Alto, California. The following is an edited transcript.

How’s your relationship with Steve Ballmer now?
He’s my Facebook [makes air quotes with his fingers] friend. I’m going to stop there while I’m still ahead.

Do you carry around any bitterness?
I’m a big believer that it’s like in The Godfather—it’s business, not personal. Netscape was an unbelievable experience for me. We sold the company for a lot of money. After that, I’m on to the next one.

I have to ask the guy who created the browser: What do you think of Google’s Chrome browser, introduced in September?
It’s very meaningful. It’s going to force Firefox and Internet Explorer to accelerate their performance. Basically, the barriers to doing everything in the browser are falling fast. And that includes a whole range of things, like Google Docs, spreadsheets, presentation packages. The Chrome browser is going to really push forward the wave.

Does this open up possibilities for companies you’re working with?
I’ll give you one example: I just announced this company called Qik. It will turn every phone that contains a camera into a source of streaming video and audio [which works better in a faster browser like Chrome]. Anybody can watch live, and then it can all get recorded. It’s almost the reverse of George Orwell. In 1984, the government had cameras mounted everywhere. In a Qik-based world, it’s the exact opposite. Literally, everybody on the planet is going to be streaming video. Excellent reason to stay at home.

And blog in your underwear.
Exactly.