How to deal with fog, condensing on the outside of glasses? I had a particularly foggy commute both ways today.  I was having to wipe the glasses lenses every 10-20 seconds as traffic permitted to maintain some semblance of visibility.

I already wear a cap with a brim/peak/visor under my helmet, but the fog is light enough to flow under with air-flow - its not like rain that would fall more downward.

Short of "wipe lots" what can be done to keep fog from depositing on glasses?
Dishwashing liquid, cheapest and best way to lose that extra liquid.

If you have a yellowish lens they make a difference with seeing contrasting low light.