try the contacts, my girlfriend wears them, i didnt even know she wore them till after like 4 months of going out with her lol, they invisable! :P
she said you cant feel them, so maybe try that?
Also, when the sweat starts running down from your helmet pads, it means its time for new pads (Y)
I used to get that problem ALL the time, but then i asked at my LBS and wiggle about how to stop it, and they said get new pads.. i did, its worked a treat :P