When you see something you can never unsee, regardless of how much bleach and hallucinogenics you use to try to forget it.
I'm a parent who usually doesn't nose into my kid's business, but, one day, I opened up my son's laptop out of idle curiosity. His browser was open, and was currently on the Google Images page of "Zoophilia." It is three hours later, I have downed THREE BOTTLES OF SNAKE VENOM, and my eyes are bleeding.
Like cutting edge, only it went slightly too far. Used to refer to technology that is so far ahead of it's time that it doesn't yet have any practical application.
For example, Microsoft Longhorn is bleeding edge because the suggested specs are so ludicrously high that nobody would be able to run it.