Lightning Photography with hacked Canons

I just learned about CHDK projekt [modified Canon firmware] which apperently offers such things as motion detection triggered  lightning photography.
You ever has tried lightning photography knows how difficult that is. The most practical approach these days would be a HD-quality movie with subsequent still extraction.
 The Canon hacked firmware projects goes a different path: Motion as trigger event is supposedly fast enough to catch actual thunderstorm lightnings.
My Powershot Pro90 IS is unfortunately not on the list. If you have had any success with this or know some pictures taken this way, post a comment, please.