This simple computer prank can leave your friend struggling with an unresponsive mouse for minutes before figuring out what's going on. When your friend is using a computer, wait until s/he leaves for a moment, then quickly slip a piece of tape on the bottom of the mouse so that it blocks the sensor (usually, on modern mouses, this is the part shining a red light). Rearrange the mouse and wait for your friend to return. Take a seat with a good view and watch your results! Many older mouses use a rubber trackball, rather than a light-based sensor. In this case, you may want to steal the ball to have the same effect as taping the sensor. However, since removing the ball can make these types of mouse feel noticeably lighter, an even better bet is to quickly remove the ball, tape over the small rollers inside the ball compartment, and replace the ball before your friend gets back. If your victim is a clean freak, this prank will drive her mad! When you go to your friend's house, bring a bottle of clear nail polish (which should be available for quite cheap at your local grocery or department store). Excuse yourself to go to the bathroom, then, when you're there, snoop around for a bar of your friend's soap or a stick of her deodorant. Carefully paint the surface of the soap or deodorant until it has a thorough (but invisible) layer of nail polish. The next time your friend tries to wash her hands with the soap or apply her deodorant, she won't be able to figure out why it isn't working! Obviously, this trick only works for bar soap and stick deodorant. Liquid soap and spray-on or roll-on deodorant can't be sabotaged this way. A little air freshener can be a good thing, but too much can make a room smell like a chemical spill. For this quick but highly effective prank, all you'll need is an aerosol can of air freshener with a trigger-style spray mechanism and a strong plastic zip tie. When your friend is in a confined area, like his bedroom, sneak up on him and subtly slip the loop of the zip tie around the air freshener's trigger, but don't tighten it yet. Get ready to run, then strike quickly and without warning — pull the zip tie tight around the trigger, throw the grenade into the room, shut the door, and run! Another old classic, this trick relies on the fact that flatulence is almost never not funny, especially when it's unexpected. This trick is tantalizingly easy — simply wait until your friend leaves her seat, then sneak a fully inflated whoopie cushion onto it, and let your friend do the rest of the work for you! To make the whoopie cushion harder to see, try slipping it under the seat's cushion. Just be sure to give the air a path to excuse or you may get a loud bang rather than the intended "noise". This prank is the louder, more shocking cousin to the classic whoopie cushion prank. To perform this prank, you'll need a loud, aerosol can-style air horn (usually available at hardware or department stores for $10-20 and under) and some strong duct tape. Remove any protective caps from the air horn's button, then tape the base of the horn to the wall behind a door so that the doorknob will knock into the air horn button when opened. Next, just wait for your victim to open the door and get a shock they won't forget! Obviously, you'll want to pick a door that this person is likely to walk through. You'll also want to tell other people who may walk through the door about your prank ahead of time. If someone else triggers the air horn, it may ruin the prank for your friend. This one's great for sleepovers. Wait until it's dark out, it's fairly quiet, and people are getting ready for bed. Excuse yourself from your group of friends by pretending you have to run home to get something you've forgotten. Then, when you're gone, silently sneak into a spot where your friends will be able to hear you, but can't see you. Start to make creepy noises ever-so-quietly. For instance, you might scratch at the wall and make whispered breathing sounds. Start out very quiet, but gradually get louder and more frequent until your friends are shaking in their beds! Top your trick off by suddenly stopping and sneaking away from your hiding spot. Walk back into the room a few minutes later as if nothing has happened. This computer prank is even more effective than the mouse prank above, but it needs a little more time. When your friend is away from his computer, take a screenshot of the desktop with no programs or windows open. If you're on a Windows PC, you should then open a simple image-editing program, like Paint, paste the image into the program, and crop out the taskbar at the bottom of the screen. Save the image and set it as the desktop background. Finally, remove all of the icons currently on the desktop. When your friend returns, his desktop should look exactly how he left it, but he won't be able to click on any of the icons! Depending on the person, this one can take hours to figure out! On a Windows PC, the default keyboard shortcut for taking a screenshot is the "Print Screen" button (often shortened to "prt sc" or something similar). On a Mac, the shortcut is Command-Shift-3.
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One-sentence summary -- Tape over their mouse's sensor. Coat their soap or deodorant with clear nail polish. Use a "Febreze grenade". Plant a whoopie cushion under a friend's seat. Hide an air horn behind a door. Freak them out with spooky late-night noises. Replace their desktop with a convincing screenshot.


Relocate them outside or somewhere else where they can receive plenty of airflow. The alcohol will soon evaporate and take the water with it, leaving your insoles clean, disinfected and smelling fresh again. Don't wear the shoes again until they've had time to dry. Doing so will just introduce new germs and moisture.
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One-sentence summary --
Set the insoles aside to dry.