I so much admire all of you who brave rainy conditions. If anything more than a light drizzle is falling, you will find me whiling my day away in the closest coffee shop or greasy spoon!
But when it is not possible to escape the rain, I don a Gore-Tex cycling jacket (with armpit zips, which I regard as indispensable) and a pair of hermetically sealed plastic cycling pants (which do a reasonable job of keeping out the rain and an even better job of keeping in every drop of perspiration!) My shoes never seem to get more than extremely damp (perhaps because of my fenders?) I wear synthetic socks that wick away moisture. (The reason the last sentence sounds like advertising copy is because it probably is.)
I almost never ride in monsoon-like downpours, unless I have very close to my final destination and am not overchilled. I never ride in thunderstorms.