I need! Same for the GPS wireless.

Hmm, so I'm watching something interesting. I hit the button and I get the previous 30 seconds....

But what if the 'interesting- started 45 seconds ago? I'd want to be able to key in an N-multiplier for the 30 sec blocks....

I think even Mann's ENGwear (Electronic News Gathering) systems can't do much more than a < one min into the past, and that's on a Pentium with fast large hard drives. It's really a matter of your reaction time, which is part of the idea of starting recording when your pulse rises or you break out in a sweat. Start when the autonomic nervous systems engage, so you don't even need to decide. After all, you can always delete it later.