Fab founder Jason Goldberg

Boosting your valuation by $175 million dollars in six months? Nice work if you can get it. Almost immediately after pivoting from a social network for gay men into a flash sales site for well-designed furniture, jewelry, and other items, Fab.com picked up an $8 million investment at a $25 million valuation. But its latest round of funding puts those already bubbilicious numbers to shame.

Andreessen Horowitz, never a VC firm to shy away when the valuations get sky high, just "plowed" $40 million into Fab.com at an astounding $200 million valuation. At this rate, it'll reach a billion by, oh, let's say next Christmas?

Despite the low barrier to entry in flash sales (hence all the Gilt Groupe competitors and verticals), Andreessen Horowitz says the valuation is justified by the company's impressive growth. In the week around Cyber Monday, Fab.com, which claims 1.2 million registered users, did more than $1.1 million in discounted deals. In November, it doubled orders for the previous month up to 100,000 and now averages $1.4 million in sales per week.

"The thing that caught our attention was the extraordinary early traction," said Jeffrey Jordan, a general partner at Andreessen Horowitz who will be joining Fab.com's board. "We think there is a really big business in aggregating the world's designers."

We hope their holiday party is pivot-themed.