I've put together 14 high-quality original podsafe instrumental tunes from my Penmachine Podcast into a CD album you can buy. It also includes a bonus data DVD with a bunch of cool stuff that isn't on this website. Find out more...
Over at the shownotes for Adam Curry's Daily Source Code, here is a list of public domain Christmas music, which is therefore podsafe, and which anyone can record without worrying about songwriters' royalties and the like.
I think I'll do an instrumental Christmas tune for my Penmachine Podcast when the season comes along. Perhaps "We Three Kings" (not in MIDI style)—I've always thought that was a fantastic melody.
We occasionally break into a wicked surf version of "God Rest Ye Merry Gentlemen" in The Neurotics, but I'm not quite sure I could do that justice by myself.