I have a much less cost effective version that sounds an alarm when anyone goes near the shed, in the garden or walks past the garden gate 10 yards away. Very effective at deterring unwanted visitors. Also effective against canvassers, junk mail, the postman, deliveries, children, guests, parents and occasionally me. Built in paper shredding function with extra capacity available for ornaments, remote controls, fingers and ankles. No off button. Needs regular maintenance.
Loki by
Bob Goddard, on Flickr