This video came from SNL and has been floating around the net for some time. This is from its Wikipedia page:
"I'm on a Boat" is the third single off The Lonely Island's debut album Incredibad, and was also featured as a Saturday Night Live Digital Short. This song features R&B singer T-Pain. The song is a parody of many rap video cliches. The music video reached number one on YouTube in February 2009 and was number one on the U.S. iTunes music video chart.
Here is the official video:
This video itself is funny. But after you watch it, check out this from CollegeHumor!!