I came at this via the Shrek version, which I liked a lot, then a friend gave me the Buckley version, saying it was much better (which IMO it is; I like it as a sad, messed up song, and I constructed a very messed up story from bits of that version).
I kind of knew Buckley's wasn't the original (I think from you posting about it) but never sought out other versions. I think I shall hunt some down on the iStore now. I'm curious to hear the original, and also to hear other interpretations.
I like the idea of a song that can be taken from many angles, can mean many things to many different people (or many things to one person). I like it when art does that.