Exactly what happened to me. I interviewed with a company from a position of weakness (I had been out of school for several years and worked as a recruiter the

Exactly what happened to me. I interviewed with a company from a position of weakness (I had been out of school for several years and worked as a recruiter then Katrina hit, so I was flat broke and out of a job for a year) and I was looking for my first real programming job. They had me build something for them that they decided they needed but that no candidate had been able to create so far. I built the tool in a couple of hours, learning the language along the way. They turned around and used the tool in production without compensation.