What's the best/worst novelty DLC (or LOL DLC as I like to call them) ever in Rock Band?

Here's a collection of some of the songs I'm talking about...

• SpongeBob's Greatest Hits
• Never Gonna Give You Up by Rick Astley
• Amazing Horse by Weebl's Stuff
• Poker Face (cover) by Eric Cartman
• The Guild catalogue
• Parry Gripp catalogue
• Flight of the Conchords catalogue
• My Name's Horatio, You Got Me, You Ain't Got Nobody Else, So Deal With It, And Love It by Mega64

So check out these songs, or if you already have, then go talk about them.