This is new, but might seem useful at times.
"IBM developerWorks offers instructions on how to interact with your computer by whistling -- that's right, whistling.
Use Linux or Microsoft Windows, the open source sndpeek program, and a simple Perl script to read specific sequences of tonal events -- literally whistling, humming, or singing at your computer -- and run commands based on those tones. Give your computer a short low whistle to check your e-mail or unlock your screensaver with the opening bars of Beethoven's Fifth Symphony.
This method isn't for beginners - it requires modifying several scripts and it takes about an hour to complete. Looking for more hands-free tricks? Checkout how you can play with your computer using Bluetooth interaction and speech recognition. This definitely brings new meaning to the adage, "whistle while you work."
Whistle while you work to run commands on your computer [IBM developerWorks]" (Lifehacker-Kyle Pott)
