I thought I'd try capturing my other hobby, woodworking. I set up to use the flash to freeze the saw blade, using a 580EX at 1/16 bounced off an umbrella. The camera setup was 500D, 17-55 @ 55mm, 1/125 @ f/3.5. I had my 430EX in slave mode set forward, bounced off the ceiling to illuminate the background. The main trick was to have enough light in the room to use the saw without cutting off my fingers, but not enough to blur the blade. The umbrella was about 3 feet away from the blade, so I was able to use 1/16 flash (shorter duration).
I'm fairly happy with the DOF, background, and reflections, but I wish there was some sawdust. I turned off the dust collector, and raised the blade more than usual, but no luck. I didn't have any scraps of oak around big enough for the shot (this was poplar): I think that might do better.
C&C most welcome.