If you're a fan of eating and playing around on the internet you've probably covered your trackpad in a thick layer of greasy finger-residue from snacking on chips. Reddit user LukeTheAlright slaps down a post-it note over his trackpad to keep the grease from soaking in.
A post-it note works great because it's thin enough that you can still use the trackpad as normal. The benefit comes when you take it off and notice it's now translucent because of all the grease, but your trackpad is still as clean as ever. This might come in handy when you don't have chopsticks on hand.