The Founders Fund is one of the more interesting tech investment funds, and not just because it's tied up with Peter Thiel and the PayPal mafia, nor just because Thiel is an investor in Vator.tv. Nor because angel partner Dave McClure will be one of our judges at Vator Splash next week.

The fund's portfolio is full of household names, though it remains pretty small. The $107 million it raised according to SEC filings today is less than some tech companies are raising in a single round.

The firm's portolfio includes Facebook (from way back in 2006, in the company's B round; Thiel was the company's first outside investor before that), Slide, Quantcast, Gowalla, Clickable, IronPort, Yammer, Mint, YouNoodle, Worldly Developments (makers of Plancast) and many more.

This is the firm's third fund. It raised its first $50 million fund in 2005 from select individuals, and then raised another $220 million in December 2007 that included undisclosed institutional investors (the WSJ reported that Stanford's Endownment was one such--a likely scenario given that it's Theil's alma mater). The half-sizing of this fund is par for the course in the VC industry, which is shrinking to about half the size it was in 2007, due to widespread cutbacks in the amount of money big endowments and pension funds are allocating to risky investments.

(image: left to right: Peter Thiel, Ken Lowry, Luke Nosek, Sean Parker)