I keep finding articles talking about App Zapper, App Cleaner, App Delete and more; but all of these programs require you to open the application to use them, "just drag and drop." But, personally I hang on to every bit of dock space I can, I put as little as I can into my dock and don't want to have to open an application to delete something, or leave it open.
That's where AppTrap comes in. It is a preference pane that runs in the background and integrates right into your current trash can. Drag the application to the trash can and it does what all these other programs do, without opening another program.
Give it a try, once you use it you won't go back.