what about the new sulfur-plasma bulbs? Ill have to find a link because I cant remember where I saw it...
they demoed one to show the range of intensities (like 5%-95%) once at the university and we all saw spots for a while
really, I find the lighting interesting because its usually the easiest "upgrade" we can make to a tank
but really Im trying to find a way to upgrade the light in my projector from teh standard halogen/xenon/whatever bulbs to a high intensity LED (tho LEDs lack the throw distance :-/- but one day Ill buy 1 $200 bulb thatll last 20years)