SAN FRANCISCO - In this tough economy, Valerie Whitlock uses two forms of currency: money and barter.

The 37-year-old actress and writer from Los Angeles holds down sporadic film and television gigs to cover her rent, utilities, car payments and insurance. For everything else - head shots and haircuts, clothing and cut reels - she trades her handcrafted jewelry.

She started swapping for goods while at work on the set. But now the classifieds Web site Craigslist and her MySpace page for Fancy Pants Jewelry have become great places to find even more trading partners. Her best scores include microdermabrasion treatments, a used Apple G4 iBook computer and Marc Jacobs jeans.

"Jewelry-making has become a creative outlet for me as well as an extra income and barter tool," Whitlock said. "It has made a huge difference in my life."

As the financial crisis makes cash and credit increasingly scarce, the ancient custom of bartering is booming. Cost-conscious consumers are getting creative to make every dollar count.

Some are dusting off books, DVDs, video games and other little-used items to trade for necessities or gifts. Others are exchanging services such as house painting for Web design or guitar lessons for clerical work.

These newly minted cheapskates are seeing the world through green eyeshades, cutting costs wherever and whenever they can.

"In the last couple of months, it's been like a bucket of cold water in our faces," said Mary Hunt, founder of money management site DebtProofLiving.com. "It has woken us up. We are paying attention to what things cost."

Every recession triggers bartering, economists say. But the Internet has given the practice unprecedented reach. Before the Web connected strangers from anywhere, bartering was limited by geography and social circle.

As a form of everyday currency, bartering has downsides. It's far more time-consuming and tricky to negotiate the exchange of goods and services than it is to simply plunk down some bills. Sometimes prospective swappers flake out or try to rip off their trading partners. Transactions don't always go smoothly.

Plus, there are potential tax liabilities. The Internal Revenue Service considers income from bartering taxable.