Aside from glasses anti-fog protection products, there is a face mask that is made by Glen Lindeman, I think, Buck Wing products, advertised as fogproof, and it does work passably, if you make certain to pinch the soft metal frame tightly against your nose below your glasses. I went to contacts this year, though, after years of fogging up.

i used to have this problem alot, but then i started using the metal framed ones like snowdog is talking about. those definately help alot. i also switched to contacts but i have yet to try them hunting. when i get up early i don't like to have to put them in early in the mornings but that's just me. contacts do make a big difference though if you don't have a problem touching your eye. i got used to it pretty quickly.

I have used the anti-fog stuff before and on certain days when the humidity is about 90% and you have just topped on of these Ozark ridges around here mine still fog up when I pull my head net down I have had mornings I had to pull my glasses off to see, then put them back on and they are fogged again in just a few seconds. Contacts really cured that problem, also you are not having to pull your glasses off to use your bino's, I don't have a pair that you can use while wearing glasses and its really aggravating to have to keep pulling them off everytime you want to look at something.