Two of the most popular things to do on the Web are play games and watch videos. Popjax, a startup backed by Shasta Ventures and Draper Fisher Jurvetson, combines the to to create a new form of casual game: video trivia. The company creates mashups of its own trivia questions with embedded videos from YouTube.

Now it is going after rock bands to create branded video trivia games for their fans. The first band to create a game is Avenged Sevenfold. If you are a heavy metal fan (and I know that you are), you can play the game here. The band will also embed the game on its fan site and MySpace page (where it has 719,000 friends). It keeps fans on their site longer and Popjax splits the ad revenue and affiliate sales fees from the application with the band.

Now how about creating a trivia game for a band I actually listen to? (I know, I’m old).