Currently, I Love Free Concerts is holding a contest to win a pair of tickets to Green Day's show on April 6th at the Mohegan Sun Arena in Connecticut.
From my understanding it looks like there is actually two ways to win tickets.
Correction: It looks like the only way to enter is to fill out the form on their website, sorry about that guys.
Good luck to everyone who enters!
Thanks to Walking Contradiction on the forum for sending this news.