D/load of the day: Keyboard Cleaner (Mac)
I created Keyboard Cleaner. It comes in handy when you want to clean your keyboard, but you are afraid you might trigger a command or change or delete some of your current work beyond repair and undo. Of course you could save and close everything. Sometimes however, it is just not what you want.
Enter Keyboard Cleaner. It shields your desktop and intercepts every keystroke you might accidentally make — except for Command-Q.
via jan.prima.de
It also blacks out the display so you can easily see the smudges on the screen and wipe it off. I've asked the developer yesterday and he confirmed it's compatible with Leopard, Snow Leopard and Lion. I tried it and it works. Smart little free app.
There's also a similar app for Windows 7 called Clean 'n' Go. It is not free though and I have not tried it so I can't vouch for it.
Happy cleaning, y'all.