I use a pair of industrial safety specs, and part of their specification is anti-fogging. So far I have had no problems. I don't think it is any special coating but rather a good ventilation system on them...
Pulsar Safety Specs
I have the mirrored for summer and the clear for night or winter. They look quite sylish as well, without the Oakley price! I am constantly plauged with watering eyes, no matter what the weather, these do stop the problem. Also... in the UK we use a combination of rocksalt and grit on the roads in winter and sometimes the cars will throw this stuff up.... these just give me a bit of peace of mind as regards a peice hitting me in the face.