Not any specific one, but I was a huge fan of Frank Jacobs, I guess he wrote the plurality of the song parodies for MAD, Sam Hart, a few others, but that was also where I was first exposed to the art form of song parodies.
I was a huge fan of 'Mad' magazine when I was 11, 12, 13 years old. I'd scour used bookstores trying to find back issues, and I'd wait at the newsstand for a new issue to come out. My life revolved around it.
I suppose I had my rock star fantasies while I was singing into my hairbrush in the bathroom mirror, but I never really consciously said, 'OK, this is what I'm going to do for a living and I'm going to be Weird Al.'
So that's why one of my rules of parody writing is that it's gotta be funny regardless of whether you know the source material. It has to work on its own merit.
It's hard to really articulate what the parameters are that make one song parody-able and another song not, but if I can come up with a good enough idea for it, I go for it, and if not, then I have to move on.
In a genre where most of the artists are one-hit wonders, I've been able to hang around longer than most "serious" acts. I pride myself in being a very talented leech.
There's a lot of different ways that a song would be a challenge to parody. There are a lot of songs that would ostensibly be a good candidate for parody, yet I can't think of a clever enough idea. Some songs are too repetitive for me to be able to fashion a humorous set of lyrics around. Some songs flat-out just don't work creatively for me.