I don't really think there's a overarching theme or link to reality in Salad Fingers. It's just a fucked up vision. And it's actually not nearly as disturbing as a lot of people find it to be. I haven't checked that site in forever.
I always liked the Burnt Face Man series a ton. Bastard Man ftw.
My favorite one is probably pjtkibj, or whatever it's called.
Somewhere on www.fat-pie.com