I've been a fan of his for a very long time. He was really the first artist I would say I was a fan of growing up. "Yoda" is my favorite, and not just my favorite Weird Al song but one of my favorite songs in general as well.
One cool thing about listening to Weird Al is whenever you first hear the parody of a song before you hear the real version. Then you are confused when you hear the real song and easily screw up the lyrics in your head.
I had the privilege of seeing Weird Al live at the Illinois State Fair back in 2008. I'm a huge Al fan, and the concert was terrific! Everything he does is downright hilarious, and I just got his new album the other day. It's great!
He's a genius, has been for decades. Unfortunately these days there are a LOT of parodies on the web which are wrongly credited to Weird Al (none of which were listed in this thread ). Anyway, my contributions of actual Weird Al songs: