Here's something that even most tattoo enthusiast consider a little extreme: eyeball tattooing.

Apparently, you can tattoo an eyeball (it has been done on blind eyes to "hide" corneal defects). In this case, Pauly Unstoppable, Josh, and Shannon Larratt tattooed their pefectly healthy eyes, just to see if it could be done.

Link: Three Blind Mice at BME, Update on Josh's eye, Update 2, Shannon's Blog entry - Thanks esa!