TeePeeing (also known as Tee-Peeing, TPing, and toilet-papering) is a prank where someone throws rolls of toilet paper all over somebody's house and yard. When done properly, the toilet paper flies around like ghostly white streamers and gets itself draped over everything that can be draped over. Cars, trees, houses- it's all good.
Like egging, TeePeeing is usually done around Halloween by snotty teens and college kids. Not only is the toilet paper really hard to clean up, but if the victim doesn't find out until morning, then the dew makes it nigh impossible to clean up as the paper deteriorates into mushy glops of mush. Toilet paper strung in trees is especially hard to get rid of, as it gets tangled in the branches and rips and just makes a mess.
Reserve this prank only for people who deserve it, like that guy who leaves his car in front of your house and doesn't move it, even when you've left a note, or for that lady who only gives out one piece of candy per trick-or-treater and makes fun of you for being too old to dress up.