Here’s my story.
If you don’t like its start, don’t miss its end.
I already knew of most of the applications in the Parallels Bundle.
I already own Hazel.
I already own a competitor app to Parallels (Fusion).
Update 2 (2008-12): MacApper posted a review of CleanApp 3, which has been released a month ago, and it looks even much more interesting than it did before. I’m yet to try it, though.