Addiction - When you can give up something any time, as long as it's next Tuesday.

Cocaine - Peruvian Marching Powder. A stimulant that has the extraordinary effect that the more you do, the more you laugh out of context.
Depression - When everything you laugh at is miserable and you can't seem to stop.
Heroin - A drug that helps you to escape reality, while making it much harder to cope when you are recaptured.
Psychosis - When everybody turns into tiny dolls and they have needles in their mouths and they hate you and you don't care because you have THE KNIFE! AHAHAHAHAHAHA!”