You can safely file this under "things that are cool to show off to your friends, but you will probably never actually use." A relatively new app called Prox is starting to gain some popularity in the Android Market, and for good reason: while running in the background, the app lets you control your HTC EVO using hand gestures, without actually touching the screen.
There are free and paid versions of the app, which differ mainly in the amount of gestures you can perform to control your phone.
The free version, Prox Lite, uses the EVO's accelerometer and proximity sensor to sense different hand gestures, which allow users to view the notification bar, go to the home screen, launch the internet browser, or open the phone application.
Prox Pro (available for $1.50) takes away the ads and expands functionality, allowing users to launch more applications, turn off the screen, toggle the ringer mode, or play a tone. Additionally, the developer is working on bringing more actions in the near future.
Importantly, Prox functionality is disabled during phone calls, so there is no need to worry about accidentally controlling your phone with face gestures. The developer also provides a video tutorial (see below) for those who might need some additional guidance while getting used to the app.
As the developer states in the app description, "You can get that real Jedi feeling and impress your friends when you launch the browser without touching the phone." If you feel so inclined, give the free version a try and let us know what you think!