Hmmmmm....Let me see.
In no order of importance.
Collar, Spanking (Hard), Pulling Hair, Rough Oral, Tieing Down, Asphyxiation, Name Calling, Pinching, Humiliation, Play Rape, Biting, Nipple Torture, Pussy Torture, Extended periods of dildo play, Orgasm control, Gagging, Long anal session where vaginal stimulation is denied, Kneading of the thighs and ass, sexy lingerie. gagging by placing my fingers in her mouth, butt plugs.
After play bruises and marks! My sub looks at these as though they are trophies the next day. That gives me a sense of pride.
I would like to add though that none of this is a turn if i can sense that my partner is not in the mood to "give".
I guess the ulitmate turn on for me is seeing the boundaries to which I can push my sub, knowing she wants those boundaries pushed.
I digress.