Hey man, do you know about "A Very Special Christmas"? It's a charity CD collaboration of a bunch of artists and they do Christmas songs.

There's a few of these albums, 5 in all, spanning 1989 to 2001.

#1
#2
#3
#4
#5

The first album has the highest rating, but I like #3 for Smashing Pumpkins and Chris Cornell singing "Ave Maria." Too bad he's playing with Eleven on that track (oh well, he'll be singing with "Rage" soon).

Anyway, check those out and let me know what you think. I might be missing the type of song you're looking for completely.