noun: busman's holiday
1. a holiday or form of recreation that involves doing the same thing that one does at work.
As well as being my job, web development is also one of my main hobbies. I often get hare-brained ideas for sites and by the time I've convinced myself that they're no good, I've already built enough of the site in question that I have to see it through. You can see examples of such lunacy and other work that I've actually been paid to do below: