Novelty Christmas songs
I have always enjoyed the dogs barking Jingle Bells, but the other day I heard Christmas Dragnet, which although not a song, was quite entertaining. Performers included Daws Butler doing his Huckleberry Hound voice for an elf & Grudge the guy who did not believe. It was basically an audio parody of Dragnet, but even those unfamiliar with that would enjoy it.
Another truly weird one is the Monsters' Holliday by Boris Picket of Monster Mash fame. Here, Frankenstein's monster, dracula et al are about to rob Santa, but have a change of heart.
What are your favorites?