That is pretty cool, I think I was under what you picturing, golf ball hail in my yard last night.
How do you do that picture every 10 seconds thing? Is that programmable in your DSLR, or is it a separate accessory to the camera? I've been wanting to try some time lapse too, but doing a video like you said creates a monster of a file.
Also, once you have all the frames compiled, are you using a software to combine them into a movie?