Tired of watching the Joker ransack your town and having no way to contact the Batman? Jealous of Commissioner Gordon's massive bat-signal, but have nowhere to keep one of your own? Then you're in luck.
Over at Thingiverse, a user named wizard23 offers step-by-step instructions for building a more compact but fully functional bat-signal—and it's one small enough that you won't need a police headquarters' rooftop to store it on.
Now if only someone would get cracking with schematics for Jimmy Olsen's ultrasonic signal watch! Because if Lex Luthor ever invades, calling the wrong superhero could be deadly.