StickyWindows is an app I thought I would like, but after nabbing and grabbing windows and generally distracting me from my work, I decided to uninstall it....
...except that I couldn't. Searching through the Applications folder yielded nothing. Searching through Applications Support in the Library yielded nothing.
The app was there in the Preferences Pane, so what I did was find the file in the Preferences folder and delete that. I'm not sure if there are other pieces lurking around my hard drive still, but I found that experience supremely annoying.
Bad on you, Donelleschi!