I've switched to AppTrap. Both find roughly the same data (still far from everything, but I realize that's an impossible goal), but AppTrap is passive, and asks whenever you delete an app. This does other program types, so I keep it around, but I rarely fire it up now.

2.0 was a much-needed update, though it didn't improve the associated-files finding at all, and might be missing more than earlier versions, though that's just from a few tests.

I Used AppCleaner and its really good too but AppZapper has a lot more things and the search system is a lot better.
If you don't have it, download it and download the full version because with the trial you will have 5 Zap's only. (A Zap is 1 uninstall.)

AppZapper is a really great App. It works better than other application uninstallers and is way cooler too! With 2.0, AppZapper now has lots of new features. You can browse your apps by date last used, size, and much more. You can even search for apps to delete from inside the app. AppZapper is very quick and snappy and when you delete something, you hear a "ZAP!" sound that, if you want, can be disabled in the preferences. AppZapper also uninstalls widgets, preference panes, and other files cluttering up your library folder. Another new feature in this version is the "My Apps" window. With this, you can drag apps you have purchased into the window and then type in your serial number for that app so you don't lose it. My apps is a great way to keep track of your purchased apps. AppZapper is animated nicely and works great. A few features I would like to see added are having a helper app that deletes apps you put in the trash and a mode that saves an apps preferences for later, in case.

This application jumped the shark when the automater stopped working in Leopard. AppCleaner is a superior, and free, alternative.

This used to be my favorite, but has now been replaced by AppCleaner which although was buggy and too flashy in the past, is now a rock solid contender with a very handy SmartDelete feature. My suggestion is to try them both out before you decide on either one.

AppZapper is better than using any other alternatives..

I used to use this until I bought Hazel. Hazel will do the same thing with its app sweep.

Appdelete is a good uninstaller top, and it is FREE!!

Still think this is a solid app. It was the first real contender in un-installers, and don't forget it does: preference panes; widgets; screensavers, etc too

I thought AppZapper was indispensable – until I found <a href="http://osx.iusethis.com/app/apptrap">AppTrap</a>. Now I can delete an application with +backspace without worries.