On a related note, it's funny that "issue tracking" is somewhat constrained to software development (or, put another way, the software development domain has some of the better tools for the task) when it's really applicable across industries.
Several years ago I put together a very-slightly-modified version of Trac (http://trac.edgewall.org) to keep track of maintenance issues with a vehicle fleet. It's worked nearly flawlessly for years and serves the purpose extremely well.
Are there any commercial projects that have taken this approach? "Software-style issue tracking for brick-and-mortar businesses"