I seem to be in the minority, but I feel that Deerhoof's album Vs Evil is way too overlooked.
I think the world sounds & polyrhythms on it are amazing. It took me awhile to really get the album, but after I got into it & also saw them play it live, I realized how impressive it was.
http://www.youtube.com/watch?v=9aNgSMvF_bo
http://www.youtube.com/watch?v=zSABSfnDmzA&ob=av2e