Scratch that, my driver side head light it taking on some water and fogging up. Belive it or not, it literally started happening the same day I posted my reply before this one, about 30 minutes with the high beam and signal on, it never completely gets rid of the fog, but most of it.
I will be on the same project as you now, I will start by getting some clear silicone, I have a silicone gun so it should be no problem, there is a vent for out-letting the water, so sealing up the lights then running your high beams a lot should get rid of the fog inside.
Old Car: Chevy Cobalt 2006 LS Sedan base (Automatic)
New Car: Chevy Impala 2011 LT Fully Loaded (Automatic)