Also, I know the R500 has the better power:weight, but it looks like the F430 is able to pull away on the straights. Either the F430 is finding a better gear and finding it faster (paddle shift?) or the aerodynamics are really penalizing the R500, even sans windscreen.
The R500 is awesome, but I'd settle for just about any new Caterham, complete with weather kit because by god I would daily-commute with that thing.
Funny picture, by the way.
A rock hammer is more common and traditional, in my experience, but hey that would weigh a lot more than 2.5g. Pretty neat, regardless.
My guess, and what I would do, is heavily reinforce the bottom and sides of the can (multi-ply steel, perhaps with sand or concrete in between layers) and design the top/lid to detach easily, so in the event of an explosion there in, the blast would be vented directly up and out of the can (basically making it into a cannon). The concussion from the blast could still break windows nearby, but otherwise wouldn't cause much damage.
Shots at ISO 800 or 1600 (the highest available ISO on the XT) are practically unprintable and only used as a last resort, which happens too often since I don't have any L glass or image stabilized lenses.