Obviously, this (which I have heard called "The Internet's Favorite Song" on more than one occasion) is the song to which I alluded in the post title; so, it's not particularly off topic. I suspect that, going forward, the Weezer/Yankovic cover will be considered the second most definitive version after Toto's original recording.

My personal favorite cover is a toss-up between this one by a Harvard University percussion club

and this one by Irish secondary school students.