Nipple Safety Pin- and leave it in for 24 hours.
I did that once, tough dare :)
do it again- you'll be twice pierced.
haha, I removed it after a month. I was scared that it might get infected.
If you have the balls (literally) go for it. (I'm not sure if we are allowed to show a female teet yet so... sorry ladies)
if you're a dumbass and you know it, pierce your skin :) *clap, clap*
Do it as many times as you can handle the pain. Bloody nipples rule!