I did it once. It's like a massive rush of power and euphoria. All your senses are amplified and you feel ten feet tall and invincible. The comedowns a bitch though. once the euphoia wears off you feel normal except that you can't sleep. The lack of sleep really fucks with your head. I've seen people have delusions that there wear people stalking them, that family members were plotting to kill them, and have crazy hallucinations of ghosts, nioses etc.

Meth is some messed up shit.