I've got one. I find it helps me sort out and prioritize which items of junk I'd really like to own, which are merely interesting, and which are just crap that would become attic fodder within ten years. Over 300 items on the list, consisting mostly of movies, photographic gear, and some books. I don't seriously think I'm going to be buying all that shit (not in today's economy, anyway), but it's still fun to keep a list. (OCD-induced hobby?) If I see something that might be useful in the future but I'm not ready for it yet, I just add it to the list so it'll be easier to find again later.
Interesting things about it... You can keep several lists, for example a main one and then several smaller ones (e.g. items needed for projects you might have in mind). You can make some public and some private. (The main list is public but with an alias instead of my real name.)
Anyone else here do that?