For punishments, setups that make you hurt yourself while you reflect on why you're there are effective: stretched out flat on the bed with a boiling hot hot water bottle under your ass, holding a big weight in each hand clipped to your nipples, wooden pony riding (http://bdsmpornvideos.com/wooden_pony_torture_img2.html - you don't need anything so elaborate, a 2x1 roped to two chair backs is fine for a start). Anything that makes you struggle against the pain and keep losing and getting hurt, while your Dom plays with you and enjoys your desperation.

If you have the space and resources for more elaborate setups, your Dom could set you to work out on a treadmill or staircase exerciser, with nipple chains and/or crotch rope positioned to hurt you if you don't keep up.