DesktopSweeper at The Apple Blog
Amos Moses Griffin likes DesktopSweeper too and mentions it in his Quest For A More Mindful Mac, at The Apple Blog:
"DesktopSweeper hides the ugly sores on your desktop. Hitting Cmd-Return (it can be changed) turns your screen into blissful, serene emptiness. Hit it again and you’ll be reverted back to your urban jungle. Think of DesktopSweeper as your Holy Rod of Power. One quick flick and it smites into oblivion everything before it."