Jun. 16--Imagine a lake formed by all the sweat equity earned by workers at Silicon Valley startups. Now imagine that lake frozen and dotted with shivering techies who can't figure out how to turn their equity into cash for a new coat in the coldest recession in generations.

Now a startup called SharesPost is trying to light a fire in the frigid economy with a novel members-only marketplace for willing sellers and buyers of shares issued in advance of an initial public stock offering, or IPO.

SharesPost debuted late Monday, coming out of a private beta with an initial transaction of 2,500 shares of Tesla Motors at $10 per share. Tesla, dubbed the "poster child of green mobility" on a research report published for SharesPost subscribers, was valued just over $1 billion in the deal.

Anticipated soon: Deals and valuations involving such startups as Facebook, Twitter, LinkedIn, Linden Labs, Ning, Slide, SolarCity, SugarCRM, XDx and others.

Early reviews from Silicon Valley observers are mixed. Adeo Ressi, founder of the entrepreneurship Web site TheFunded, calls SharesPost "the coolest thing I've seen in a while." But Larry Albukerk, the managing partner of EB Exchange Funds who helps entrepreneurs do private deals, was skeptical.

"I completely see it from the sell side. There's a huge demand to sell. But there's not a lot of demand to buy the stuff," Albukerk said. He also questioned whether buyers would feel they have sufficient

information to make the minimum $25,000 deal.

If SharesPost succeeds in helping hard-pressed techies convert equity into cash, it also figures to add some hard data to the sometimes dubious art of startup valuations, which now involves "a lot of bull," Ressi said.

SharesPost founder and CEO Greg Brogger, a former associate at powerhouse valley law firm Wilson Sonsini Goodrich & Rosati and former chief operating officer of CarsDirect, likened the site to a cross between Craigslist and eBay. Sellers and "accredited" buyers, expected to have a net worth exceeding $1 million, can interact for a monthly subscription of $34.

There is no charge for transactions on the site, which includes third-party research reports for startups and a discussion forum. The initial reports showed Linden Labs, known for creating the virtual world Second Life, valued from $450 million to $590 million; the business services firm SugarCRM at between $195 million and $252 million, and the molecular diagnostics startup XDx between $139 million and $166 million.