Anybody every try pirating parts from those cheep 35W HID flashlights that sell for about 50 bucks on ebay to make a divelight. $50 for a bulb and ballast is dirt cheep.
YES to pirating a cheap HID. Unfortunately, no (for me) for building a dive light.
Most of the larger HID lights use a 35W ballast, which means you'd have to carry significant battery weight. AFAIK most dive lights use 10W ballasts for reasons of portability, and they're still very high output.