If you're looking to add something fun to your desk, here is a little catapult that can launch anything up to the size of a ping pong ball using a fun mechanical lever. Maybe you want to take out some frustration and crumple up a ball of paper and shoot it in the trash can, or if you just need some mid-day amusement. You can print all of this in a single-plate build, or you could get creative and print the parts in different colors for more dynamic fun.
This is a great companion to the mini desk game for the filament purge contest below, which is a fun way to use your filament purges.
Fling the Poo - Fun Mini Game for Filament Purges by ozarkexpeditions - MakerWorld
Putting this together is a snap! I would recommend looking at the image below and assembling the pieces together as shown in the exploded view.
The larger pegs are shown in blue, and the smaller pegs are yellow in the image below.