(Shamelessly ripped off Uncyclopedia)
100 - 91
100. Hammering a look-alike car
This involves taking the victim's car and replacing it with an identical one. The replacement car is then smashed up. Alternatively, you can do this the other way round at the same time, as long as the look-alike car isn't yours. Result: very expensive joke.
99. Poisoning their breakfast
Widely regarded as a generally bad joke, since the victim usually dies before you can safely point out that you poisoned their breakfast. The best way of doing this is to put tiny sharp pieces of metal in. Then make them run around till they squirt blood.
98. A Borax cappuccino
Putting Borax in their coffee has a lovely effect on the look of the drink, and is even more amusing when the victim starts foaming at the mouth.
97. Stealing their credit cards
A time tested joke - you simply empty the victim's wallet of all cards and cash. Then, when out, you will invariably need money, and your victim will thus discover all his cards have been stolen. Naturally, you should only return them once he has canceled them all.
96. Impersonating the FBI
You and a friend can visit the victim's address, posing as FBI agents. You can then claim that you have logs from their ISP that they have been downloading child pornography (which is more than likely if they're a member of 4chan) and that you thus have a warrant for their computers. Later, format the computers and return them.
95. Abducting their children.
For a truly effective gag, simply abduct the victim's children before they enter the school doors. Since you abducted them before 12:00, it is OK to hold them after this time. For maximum effect, return the children just before midnight. It is also even funnier if the children are drunk, naked and anally abused.
94. Kill their pet
A particularly effective gag is to kill their pet, behead it, and then place the head in their mug. Naturally, you can make this OK by buying them a new pet; "see, it's OK, I got you a new one".
93. Impersonate their doctor
A classic joke is to phone the victim and inform them that their wife has been diagnosed with an airborne strain of HIV, and that they should probably also be tested too. For added effect, tell them that the public must be notified, but they are entitled to free counseling.
92. Get hold of the wild animal they sponsored
Clearly any animal of identical species will do; bring the animal to their door, and inform them that the Zoo has gone into liquidation, and thus, the animal is now their legal property.
91. Break into their house and redecorate
A classic one is to break into their house after they are asleep, and redecorate as many rooms as possible with purple (or striped, vibrant red & blue) wallpaper. Alternatively, you can just drill loads of holes in the walls, and insert a Cadbury's finger in each.

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