Some keys to bike comfort that I'm fond of linked to below.

What do you all recommend for cold and wet weather riding?

padded bike underwear
http://www.rei.com/product/765678

For the fellas
http://www.rei.com/product/763566

Sugoi Zap Helmet Cover
http://www.rei.com/product/756396

Sugoi Subzero Skull Cap
http://www.rei.com/product/725336

Sugoi MidZero Balaclava
http://www.rei.com/product/659704

Smartwool neck gaiter
http://www.rei.com/product/738922

And, of course, good gloves. We're just back from bikejoring in DC's wet snow. Started out with my winter bike gloves but halfway through switched to ski gloves. Bulky but toasty and dry. Have to find better waterproof and warm bike gloves.

The Sugoig Zap Helmet Cover kept by head dry and fit my Bell helmet like a glove. The skull cap kept my head warm. Marmot parka kept me dry and warm as always. That thing has paid for itself several times over. Gore-tex low-cut boots and Smartwool snowboarding socks kept my lower legs warm. Unfortunately my waterproof pants are in the teardrop trailer in the mountains so my legs got damp but we were constantly on the move and it wasn't until after I got out of the car at home that I felt chilled.

Here's a bikejoring pic from Thanksgiving week