I am always looking to maximize the dollars I spend, and to take advantage of any programs that are out there. I have noticed programs like idine.com, myrewards.com, etc. I also don't like dealing with hassles.

Which programs do you subscribe to, and why? Which ones do you hate and why? Which are worth joining and which should I avoid like the plague?

(BTW, assume that I am already in airline/hotel/rental car programs, and I have the credit card I want already, so none of those, please