If it was a challenge or for money maybe 50 or so. My triceps will always exhaust themselves way before my chest does though. I never really do excercises with more than 15 reps of anything, because the weight would be so low that it doesn't really stimulate the muscle to grow (or not nearly as quickly).
For chest I just do basically just the meat & potato excercises -- bench press, flys, cable crosses, dips, for chest but push-ups ... probably haven't done those regularily since I was a kid.
Push ups, pull ups, things like that ... any one can gradually build up the ability to do a ton of reps though, even if they're scrawny, eventually it becomes easier and easier if you do it daily. Might be a little harder if you're obese, but I find fatter guys can bench press a ton in some cases.
