Facebook, which is expected to file for an IPO this week, already has a value of $85 billion. And the shares in the Social Stock Tracker — which covers companies like LinkedIn (NYSE:LNKD), Zynga (NASDAQ:ZNGA) and Groupon (NASDAQ:GRPN) — have a combined market cap of $33 billion.

So, what might be the next breakout companies to make investors rich? Well, Mashable put together a great list:

Skillshare: This is an online destination to find offline courses. Essentially, it’s a great way to help teachers make extra money. Who wouldn’t like that?

Zaarly or Taskrabbit: They’re trying to get a piece of Craigslist’s highly profitable market, by making classifieds more mobile and safer, such as with background checks. I recently had a chance to talk to the CEO of Taskrabbit.

LevelUp/SCVNGR: This helps merchants create loyalty programs, which are available on just about any mobile device. Since October, more than 1,000 customers have signed up.

Dwolla: The service makes it easy to transfer funds across social networks like Facebook and Twitter. It charge 25 cents for payments above $10.

Eventbrite: This is an online platform for ticketing. In 2011, it looks like the company sold about 21 million tickets. An IPO filing is rumored to be coming in the next few months.

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