Quora is an $86 million-dollar company with a billion-dollar state of mind.

So far it has raised $11 million at an $86 million valuation from Benchmark Capital and individual investors.

Earlier this year it was rumored to be raising another round, but was rejecting offers that would make its valuation a "mere" $300 million.

The founders think Quora has far more potential than that.  It supposedly turned down a $1 billion acquisition offer.

Location-based check in startup Foursquare closed a $50 million round in June. That's in addition to the $20 million it previously raised.

Foursquare's rumored valuation has been as high as $1 billion, but it is likely closer to $600 million .

Last year, ad bidding network Appnexus raised a $50 million Series C round.

It has raised $65.5 million so far, and is well on its way to a $1 billion valuation.

ZocDoc, a service for booking appointments online, closed a $50 million round from DST yesterday.

The company launched in 2007 and now has an estimated valuation of $700 million.

The music company raised $100 million in June from Kleiner Perkins, Accel and DST, giving it a $1 billion valuation. 

We've yet to see a wildly profitable online music company, though, and Spotify needs to figure out how to make money. It has to pay record labels a lot, so without a clear business model, the valuation looks airy.

TechCrunch says mobile gaming company Storm8 is raising a whopping $300 million round.  Accel Partners and Technology Crossover Ventures could be leading the charge.

If it closes, Storm8 will be bumped up to billion-dollar-valuation status.

Jack Dorsey's mobile payment solution, Square, is another billion-dollar startup.

Kleiner Perkins led a $100 million round of financing at the end of June. Now the company has a $1 billion valuation; some wonder if it could be worth as much as $2 billion.

Earlier this year, the flash sales site raised an additional $138 million.

It's on track to generate $500 million in revenue this year.

Despite all the negative press, Airbnb is doing very well.

In 2010, bookings grew 800% to 800,000; that number is increasing by 40-50% per month.

Last month it raised a massive $112 million round, reaching a billion-dollar valuation.

Private sales site Vente Privee currently has a $3 billion valuation, but its founder, Jacques-Antoine Granjon, wants that number to be much higher.

In 2010, Vente Privee's revenue was $1.3 billion. This year it is on track to do $1.5 billion. Granjon wants that number to become $15 billion by turning his site into the Amazon of Europe.

Dropbox closed a $7.2 million round in 2007, but it is rumored to be raising a more substantial round now.

TechCrunch heard that the file storing/sharing company is raising between $200 and $300 million.

Depending on the final number, Dropbox's valuation could jump from $2 billion to $5 or $10 billion.

Last year, the Angry Birds maker generated $5 million in revenue and $3 million in profits.

In March, Rovio raised a massive round, shooting its valuation up to $200 million.  It's a bit of a stretch, but if Angry Birds keeps up its momentum, it could turn Rovio into a billion-dollar company.

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