This is a video of science teacher Bruce Yeany demonstrating and discussing string-shooters, little motor-driven wheels that keep a loop of string suspended in the air thanks to inertia. That looks like fun, I kinda want to build one myself. Will I wind up getting my neck caught in the loop and accidentally strangling myself to death while my parents are at work? *shakes magic 8-Ball so hard the fortune telling cube comes out and I choke on it and die* Ghost Me: Well I guess that answers that.

Keep going for the informative video.

Source: Geekologie – Coooool!: Physics Teacher Demonstrates String-Shooters