My snakes get light from the window and that's it. I had lights installed when I got my cages from AP.com but I noticed when they were on my snakes went hiding. When I leave them off they tend to still hide but do come out a little more. I leave all my lights off and pretty much only turn them on for display when people come over.
Heat, I close my ac vent during the day and open it up at night. The room gets to 82F or so. (no added heat in the summer)
I replaced my AC unit with A TRAIN 21seer and have seen my bill drop. I'm also waiting on GE's Hybrid Water Heaters later this year.
http://www.groovygreen.com/groove/?p=2901
I've done all the light bulbs, Prius 08 etc... Next I'll tap into the neighbors electric line lol! J/K