7.2 Megapixels In Your Pocket:

One of the coolest things about the video capabilities, however, is what people have been calling “Tivo-mode”. In this mode, I can keep pointing the camera for however long I wish and when I hit the shutter button, the camera begins recording from 5 seconds in the past. You can imagine how useful this is when you’re at an event and you want to catch the action but you’re not sure exactly when that may be. Why waste recording time when nothing is happening?

I’ve been wondering for a while why every camera doesn’t do that — why everything doesn’t work that way, now that we’re technically capable of it (at the expense of battery life, of course, in all cases where there’s a battery).