Ugly Christmas Sweaters on Amazon (US)
They are the most hilarious things and I can see fanfic about them. One has a reindeer menage a trois, another has a gingerbread nightmare. There is a link to them off of Instapundit or if that site makes you want to spork your eyeballs, just search Amazon (US) for the phrase Ugly Christmas Sweaters. That's actually a company name.