I usually try to refrain from posting bootleg trailers, but this one is actually pretty decent quality so I thought it was worth putting up at least until an official version finds its way online. Monsters vs Aliens is an upcoming Dreamworks 3D animated film from Rob Letterman (Shark Tale) and Conrad Vernon (Shrek 2). Although that in itself doesn’t really excite me, the concept is kind of cool: when aliens invade Earth, the U.S. government recruits a number of freakish monsters to fight back for them.

Basically it’s a send up of old b-movies with a decidedly Monsters Inc vibe. The voice cast includes Seth Rogen, Paul Rudd, Rainn Wilson, Reese Witherspoon and Will Arnett… plus Stephen Colbert voices the President of the United States of America. How can you say no to that? Monsters vs Aliens hits theatres on March 27, 2009.