I received a call from one of my co-workers in the UK the other day, looking for some help with a quick, down-and-dirty database to help him track company assets held by employees. Just something to track the details on all of the computer and peripherals, phones, cars, things like that. He already had it started, and just needed a little help getting the report built and formatted. So, being the nice guy I am, I say 'Sure, zip it up and send it to me, then I'll give you a call back'.
A minute later I had it opened up and was looking at the tables. He actually did a pretty good job, and had the different 'objects' in their own tables. He had a user table, a phone table, a car table, and an IT table. He had, however, fallen into a typical trap that novice database developers often fall into. He had set up a 'name' field in the user table, then had used that name field for the linking fields in the other tables. So what's wrong with that, you ask?