On the big screen you can stop someone from breaking into a room with a wooden chair jammed against the door. In reality, you might as well just hand intruders your keys unless you're using Daniel Ballou's specially-engineered Who's There Chair.
The back of the chair's made from steel tubing so it's extra strong, while a pair of gripped pivoting feet on the back legs help keep it in place. There's even a notch in the backrest designed to perfectly fit a doorknob so the chair stays in place long enough for you to slip out the window and safely jump five stories into a dumpster full of cushioning boxes and trash bags below—just like in the movies. [Daniel Ballou via bookofjoe]