this is the grossest prank ive ever heard of... you only do it to someone if you REALLY dislike them and you dont breathe a word to anyone...
this is known as the UPPER DECKER.
Ok, most normal toilets have all that dranage thing behind the main sitting and doing your business area right? well, if your ever at someones house and they stole your g/f or she cheated on you with the star quarterback, etc., then you can "sit and do your business" in the dranage place. just take the top off, and let the bombs drop. BUT DO NOT FLUSH THE TOILET. IF YOU DO IT SPOILS SOME OF THE AFFECTS. (you dont really have to anyways)
here are the affects.
1) after about 2 hours, the bathroom smells absuletly horrid.
2) next time someone flushes, brown **** nasty water will fill in instead of clean glimmering water.
3) it keeps in there until the person discovers it
4) they have to clean it out (this can be really difficult if it takes them a while to figure it out)
and 5) the longer it sits, the more house it makes stink.
this prank was brought to my attetion by a friend.. and we were at this *******s house party... and he did it.