A good article by Jennifer Healey and Rosalind Picard is avaliable online, titled "StartleCam: A Cybernetic Wearable Camera". StartleCam is an idea to employ body sensors to activate a camera on the person. Having recently been in a stituation where I witnessed a mother kick her daughter in a supermarket parking lot, I can appreciate the desire to trigger recording by dramatic changes in one's personal body. Perferably I'd like a device that records all the time, and would red flag pertinant data for later review, but I can undstand data storage limitations. I have wanted a wearable camera for a long time. If you're interesting in building a wearable camera, I recommend you check out Steve Mann's DomeWear which with a few other products, could produce a very effective startlecam.