Super Meat Boy! - Choice Piano Cuts is a $4.99 (or more, if you're feeling generous) collection of 10 tracks from the SMB soundtrack, composed by Baranowsky and arranged/performed by Kennedy. The purchase also includes a PDF of the Kennedy's sheet music for the entire album, which in itself is well worth the price of admission for the musically inclined out there.
The soundtrack's original arrangements are great and everything, don't get us wrong, but there's a deeper level to Baranowsky's skill as a composer that's exceptionally brought to life by Kennedy's mastery of the ivory keys. Do yourself a favor and give it a listen.