William Nelson Cromwell famously earned a million dollars for his work in selling the Panama Canal a century ago. His fee, the New York Times noted in 1908, was "the like of which can hardly be paralleled in the history of the legal profession."

News of some recent paydays probably would have Cromwell, whose legacy lives on in the top-tier Wall Street firm Sullivan & Cromwell, wishing he could get back to work.

Delphi, an auto parts maker, racked up nearly $100 million in legal, accounting, and consulting fees in the first eight months of its bankruptcy proceeding in 2006. Lawyers who succeeded in an Iowa antitrust case against Microsoft were awarded $75 million in fees and costs last August. And this March, the law firm representing one segment of investors suing financial institutions tied to the Enron bankruptcy requested a whopping $688 million in fees.

With some lawyers now charging upwards of $1,000 an hour, and phalanxes of partners and associates being marshaled to fight increasingly complex and time-consuming (read: billable-hour-generating) battles, one can rightly wonder whether the first billion-dollar legal bill could be far behind.

The fear of just such a billing Armageddon has caused some of the nation's largest corporations to push back. Some are instituting a moratorium on fee hikes, others are insisting that fees actually be slashed, and many are installing new billing software to track and cap expenses. A few are even prodding law firms to come up with wholly new compensation arrangements that better align their interests with those of their corporate clients.

Last November, the news that some new law firm associates were being paid $160,000 a year spurred Wal-Mart to action. The company responded with a "moratorium on across-the-board rate increases" for all of its outside firms and demanded that they provide the hourly rates charged for every associate working on a Wal-Mart account going back to "the class of 2004."

That same year, Tyco International named a single firm, Eversheds, as its preferred outside counsel in Europe, the Middle East, and Africa, pulling about $20 million in legal work from more than 200 other firms. Eversheds got the work by discounting fees and agreeing to let Tyco have final approval over cost estimates.

Companies like Pfizer are making strides in reducing legal costs by making law firms compete head to head for business, with cost as a major factor. Others, including AOL, Barclays, and General Motors, have embraced electronic billing systems that flag legal expenses over set amounts.