The A.V. Club has made a list of 25 songs and they are inviting bands into their office to cover them. When a song has been played it gets crossed off the list. Once a week, for 25 weeks, they release a new cover song with video.
The results so far have been outstanding.
The most recent cover song is Motion City Soundtrack covering Pavement.
My favorite so far is The Clientele covering M.I.A.