Pour some water into ice cube trays. Before putting it in the freezer, put plastic bugs in the water. Then, when the water is frozen and turned into an ice cube, it will look like their are little bugs in your drink. Or, if you want to scare someone, buy, make or find a scary mask. Then when your victim looks in the mirror, they'll see a monster. It works better when the victim just took a shower. Because the mirror will look all fogged up!