Last year, we posted about a plan to train crows to pick up litter, specifically, cigarette butts. Here's a way that can happen. The Crowbox is a vending machine for crows. It's set up in stages, to train birds how to use it, and crows are pretty smart and learn quickly. This demonstration video uses quarters, but there's no reason you can't use cigarette butts or something else that crows can easily find. If you'd like to make your own Crowbox, the plans and instructions are here. -via Metafilter