I thought this was interesting: Man puts iPhone in model rocket. Uses accelerometers and GPS to track. Unfortunately, the iPhone can't log data beyond 3G (pun intended). http://www.mobileorchard.com/the-iphone-rocket/ Years ago, I worked on inertial accelerometers for aviation, and I can say that this appears slightly lower quality... But what's interesting is that many people will now be carrying iPhones and Androids, both of which allow for easy deployment of software. This is the first time that normal people have carried 'general purpose' computers with internet access. All sorts of wacky stuff is possible. Has anyone made apps for Android (linux, java) yet? J