Warning: I've come to realize that my repeated orgasm capacity is slightly, abnormally ridiculous, so don't take this as any kind of challenge or measure of what normal people do and enjoy.
I can't vouch for the accuracy of his counting for reasons that will soon become clear, but my boyfriend claims he once sent me ripping through around 25 orgasms in a setting. He takes a feindish pleasure in something just this side of forced orgasm play, and when he gets going I end up semi-comatose. In a good way, of course. The time in question, I lost the ability to count orgasms after about 5. The thrashing and spasmimg and arching up off the couch was probably a good indicator for him of when to count a "point", hahah.
By myself, I've hit... somewhere around 10ish. No matter how hard I try to make myself count them, I start losing track after a little while, hahah.