DENVER — A blue cube, about the size of a shoebox, is bolted to the side of an apartment building in downtown Denver.
Sheltered from the elements by a custom awning and protective cage, the cube, positioned about 12 feet from the ground, is a device called the Blue Chirper. It includes a motion sensor that is triggered when someone walks or stands within a few feet of the box.
Once activated, the device flashes a blue strobe light and plays a cricket noise that is designed to alarm — and annoy — people enough to move elsewhere…