The 10 Hottest Private Companies in Tech

SecondMarket, a firm that facilitates alternative investments, has shared with Mashable () a list of private companies its buyers and potential buyers were most interested in this year. The list is based on the percentage who indicated they were interested in each company.

• 1. Facebook (): More than 25% of the firm’s buyers and potential buyers indicated that they were interested in Facebook. With the company reportedly on track to bring in $2 billion in revenue this year and attracting 81% of Gen Yers daily, it’s easy to see why.
• 2. LinkedIn (): Last month, the professional social networking platform announced that it was adding a member every second to its 85 million-person community. Earlier this year, estimates placed LinkedIn’s valuation at $2 billion.
• 3. Twitter (): Twitter finally tried to make money this year with promoted tweets, and it bodes well that beta testers are finding the new marketing channel valuable. The company just raised another $200 million that values it at a reported $3.7 billion.
• 4. Zynga: The New York Times pondered whether Zynga might be the “Google () of Games” this year. The company has more than 45 million active users on its social games like FarmVille and Mafia Wars.
• 5. Craigslist (): Craigslist makes money on recruitment listings, and it used to make money on adult services listings. Alas (for Craigslist, at least), the questionably legal section that expected to comprise about 30% of its revenue was shut down yesterday.
• 6. Groupon: Google was willing to pay $5.3 billion for the group-buying company, which has about an $800 million annual gross revenue run rate.
• 7. Yelp (): This year Yelp took new funding and challenged Foursquare () and Groupon with new features.
• 8. SecondMarket: Given that the investors who indicated SecondMarket was an interest were signing up to buy through SecondMarket, this one isn’t a surprise.
• 9. Pandora (): Pandora reported its first profitable quarter — and $50 million in revenue — at the end of 2009. Earlier this year, a Wall Street analyst predicted the company’s 2010 revenue would reach $100 million.
• 10. Bloom Energy: Building a refrigerator-sized box that can power a whole house with sand-based fuel cells will inevitably attract some attention from investors. Before the Bloom Box launch, it’s rumored that the company had already won more than $400 million in funding.

Do you agree with SecondMarket’s users? What companies would you add to this list? Tell us in the comments below.

-------------------

By Sarah Kessler