Which credit card gives you the best rewards?

I tend to use one credit card to charge all my expenses each month and then pay it off at the end of the month. There are sooooo many credit cards out there and I was wondering which one gives the best rewards back. What card do you use, and what type of benefit do you get for using it? I don't care if it is for airline miles, cash back (a percentage) or some sort of point program. I was just wondering who is using what card and why?? Thanks!

I would suggest staying away from airline cards because the way airlines are cutting back on their benefits, you may never know when they'll cancel their mileage programs. I was browsing through the following site and there seems to be some very good cash back cards. That's the best way to make your money back without having to figure out what points are actually worth. See if you like any of them.