9. Limelight Networks

What it does: Provides content delivery solutions 
IPO Date: June 7, 2007
Money raised: $240 million

You've probably never heard of Limelight Networks, but if you're an Xbox Live member, you've used its services a lot. The company uses a global fiber-optic network to help companies deliver content directly to their customers without having to use the public Internet spectrum. It helps Microsoft get all the Xbox Live content into your living room, it helped NBC stream the Beijing Olympics online, and has done work with a large number other big companies like Disney, EA Sports, and Netflix. So when it decided to go public in 2007, it was sort of a no-brainer. It sold 16 million shares at $15 to raise $240 million.