You could do a flickering effect I imagine. There are decent options for ambient light settings. I've played about with a day night thing, but was not happy with the fogging effect. I'm sure it's possible to fudge a flickering effect. I may be wrong of course, but I am fairly confident. I'll have a look when I can, although there are better scriptwriters than me about I imagine. No, actually I know, there are always better scriptwriters.. I'm more your Jack of all Trades to be fair. Definitely possible though.
SPECS: Q6600 CPU. Nvidia 260GTX. 8 Gig Memory. Win 7.