Well this got my interest pretty darn quick. I remember briefly looking into this around two years ago. I didn't really find anything, but for some reason only limited my search to the android market place. That was stupid, but I now realized that this technology is well within our reach and began searching for implementations.
The first thing I found is that the Chrome browser is a bit more friendly with webcams. I dusted off chrome and immediately found an addon app called Flutter. "Awesome now to test it out" I thought, well after installing the app to my browser it informed me that I would need to download some software to my computer for it to work; prompting me for the Windows or OSX download.
Well shucks, that aint gunna work. No worries it would have been too easy, where is the fun in that. Still searching for browser based and OS independent implementations I found a ste called Willy's Motion Control. Again this only works in chrome, but it allows you to control this slide show by simply swiping your hand in front of the camera. Now it sure doesn't work perfectly, sometimes it doesn't pick up your motion and sometimes reacts unexpectedly, but I have to give the guy, Willy, credit he did a great job. I felt very futuristic moving from slide to slide without touching anything.
That is it for now. Stay tuned because I will be testing out the Flutter application on a different computer, see how well it works. Regardless I won't be adopting it anytime soon, the OS requirements are a deal breaker.
I will be testing and looking for linux based software implementations of this concept. It looks like there is something called eViacam in the Arch User Repositories that allow you to control the mouse using your head. So a bit different than swiping your hands in front of the screen and probably a lot less work: I found myself literally flailing around on Willy's site.
Unfortunately something is going wrong when I install eViacam. Hopefully I'll get that up and running soon so I can report on it. While it doesn't look like there are a ton of different software options for this concept at the moment, I can tell we are right on the edge of something really cool (and a bit scary too). The software exists, the hardware exists, it just needs to be made personal computer and consumer friendly.