I discovered a new way to get more out of sensation play. I think pain and sensation is mostly in the head, so to prepare for play, I think it's fun to "tune in" to the area of interest before applying more interesting sensations. For example, try the most minimal touch on a nipple that you can register. So concentrate on feeling that. See if you can feel even less. Now you're set up to really experience pain/other sensations there! The same thing works with other senses. I discovered this when tasting peanut butter, actually. Taste a very small amount. Tune in your peanut butter sense. Then take a mouthful. INTENSE! I think this phenomenon is seen in the animal kingdom with bloodhound dogs, who smell a trace scent, then they go nuts when they get a better noseful.