Photoground. Unfortunately their site is under construction, but you can still see one picture! *ogles*
This is lovely, you can see how tight it's pinching his nipple, though it would probably pinch more than cut. SM can get really creative in the implements used. So can any kink, I suppose, but looking around your house for things to safely hurt yourself or your partner is pretty awesome. Do I even need to mention my fascination with hardware stores? Oooo...
I post so many beautiful bondage pictures, but I can never get enough masochism or sadism photos and art. It seems that there's less of it out there (that I find and fall in love with, anyway). My pet and I have thousands of pictures of our SM exploits, but they're all bad-quality and taken with a cheap camera by someone who's a) not a photographer by any means and b) usually in the middle of play. It's really hard to break scene and take really nice photos.
One day we'll befriend a kinky photographer.
PS- yay for nipple piercings!