I like the concept and the simplicity of this app (a single pane w/3 buttons), but it's lacking in implementation. There seems not to be a keyboard command to invoke the global hide, which requires opening the app or leaving it open before the user can perform the action. It's very light so I am launching it on login then minimizing it to the Dock except when I need it. Not an elegant approach, but since I typically run a lot of apps simultaneously I find this a sometimes-useful alternative to Exposé's hide-all command. One benefit I see over Exposé is that it does not leave a dark border around the screen edge, thereby leaving the full screen useable (in Exposé if you click on the black border it will cause the windows to re-appear). It would be much more useful if it were developed as a preference pane that could be invoked with a key command, eliminating the nuisance of having to open and/or un-minimize it before being able to use it, and the additional nuisance of the app's (small) window remaining onscreen (what's up with that?). Until then I won't use it as much as I do Exposé.