I had this as part of a weekly challenge with the following prompt: Design a makeshift weapon built out of the parts that were immediately available to you when the zombie apocalypse hit. I decided I would be in a bike shop when the zombies took over.

I designed several items. I made a knife made from handlebars and a hand brake. I also made a handheld chainsaw from a bicycle chain, and other parts. I made many smaller complexity items also, like a helmet, and throwing star CDs out of old Daft Punk and Linkin Park compact discs.