The 2010 Virgin Mobile FreeFest will be held on September 25, 2010 on two stages and a dance forest at the Merriweather Post Pavilion, outside Washington, DC. Confirmed bands include: M.I.A., LCD Soundsystem, Pavement, T.I., Ludacris, Joan Jett, Thievery Corporation, Matt & Kim, Jimmy Eat World, the Temper Trap, Sleigh Bells, Edward Sharpe & the Magnetic Zeros, Yeasayer, Chromeo, Die Antwoord, Modeselektor, Neon Indian and Trombone Shorty.

One indie band will be lucky enough to  win $5,000 and open in front of some $40,000 music fans. Cast your vote for your favorite band until this Thursday, August 19.

The lucky winner will be announced on August 31.

Tip: Don’t just vote for the “Top 20,” browse by genre, location, and alphabetical order. Mix things up a bit! Let’s make this a real competition!