Personally, I'm fond of the idea of the idea of slow castration without
anesthesia.

but that's not as bad.  the cutting(proceeding at a painful pace) could
last at most 2 minutes.

Castration *doesn't* solve the problem!  Rapists are torturers, and can 
still hurt people just as much (even if not by rape) after that kind of 
revenge.  If you read newspapers long enough, you'll see some horror stories 
involving hairbrushes, glass bottles, broomsticks...

...but if you remove a torturer's *arms* it's a lot harder for the monster 
to strike again in any way (for starters, he can't get a grip on the 
intended victim in the first place).

GREAT idea! Remove arms, legs AND use the garlic crusher. Then he can't phone
for help, can't run away if he tries anything again, and can't do 
anything by himself.

Kun-chan...