For $25 you can get these Possessed Books, which look like regular Victorian books but contain a motion detector so whenever somebody walks by the middle book will slide out. The books also emit "spooky sounds" which I imagine to be more comical than scary. If you really want to scare people, just hide in your bookshelf, and whenever somebody walks by jump out and punch them in the face.
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Instructables has a nice tutorial on how to create motorized skates using a pair of inline skates, an angle grinder, and a bag of 12 volt batteries. And just how safe are these? Well instead of brakes, this is how you stop:
In this version, I just put trust in my sense of bala... / Continue →
Who knew there was such a big market for levitating globes? This one isn't nearly as cool though since it needs a top and bottom magnet.
A magnetic field sensor continually measures the height at which the globes are suspended. This sensor feeds that data into a micro computer... / Continue →
This is a few years old, but the Furminator is a first person pinball machine that puts you inside the perspective of the actual machine:
The ////furminator is a pinball machine that puts the player in a first person perspective similar to modern "EGO Shooter" video games. Lik... / Continue →