I found the best thing for my chest was to mix it up well with declines, inclines and flatt.
Mixing it up has seemed to be a repeating theme here at the forums, I guess the more the better to stimulate your body.
A couple of years ago, when I still had a subscription to Mens Fitness magazine, I ran across something that they called the Treasure Chest routine. It used incline, flat and decline bench presses supersetted with incline, flat and decline push-ups. The trick was to target a different area of the chest with the push-ups than the one that was worked with the presses. It looked something like this:
Incline Bench presses/
Flat Push-Ups - 3X10/20
Flat Bench Presses/
Decline Push-Ups - 3x10/20
Decline Bench Presses/
Incline Push-Ups - 3x10/20
I used it as a volume workout rather than a strength-building one, and walked out of the gym with some awesome pumps.