I've got to go with Carlo Gambino. Try as they did, the government wasn't able to touch him. He died a natural death, which is no small feat in this line of work.

"After all, we are not communists"

Christopher Moltisanti: You ever think what a coincidence it is that Lou Gehrig died of Lou Gehrig's disease?

Tony Soprano: Yeah well, when you're married, you'll understand the importance of fresh produce.