Got a few minutes? Earn a couple cents with Amazon Mechanical Turk.
I tried it briefly. They offered me 3 cents to look at five pictures and select the one that looks like a storefront. Amazon sends trucks through neighborhoods, snapping photos every second or two, and now they need to pick the best ones for a database of street-view scenes. Some of the photos were clearly not appropriate (a tree was in the way, there was no store, etc.) It's the kind of task that's trivial for any human over 3 years old, but extremely hard for a computer.
The cool part is that Amazon is trying to franchise this business by letting other companies contract to their marketplace for a percentage of the fee. If you have a stash of images (or other pattern-recognition problems that humans do easily), Amazon will expose your problem to their Mechanical Turk users.
It's named "Mechnical Turk" after a famous 19th Century Chess-playing machine that turned out to really have a person inside.