Riding in the winter?

I'm in Wisconsin and also deal wiuth the snow.  My winter bike training will include:

-Two hard 60-75 min. Computrainer sessions/week (you might find these offered through a bike shop if you dont want to buy the computrainer).  I avoid long trainer sessions indoors.
-One longer ride outside on my mountain bike weather permitting (really agressive tires and foot warmers help).  These are fun.
-Strength training (Quads, calves, hamstrings, glutes, lower back and core).  Not fun b/c I don't like the gym, but the best when its a really snowy day.  Must do regularly or risk injury.
-Nordic skiing.  The skiing is probably the most useful winter cross-training that I've found.  I would pick Nordic skiing if all I could do was one thing this winter.

I live in Central Indiana and while the temps don't quite go down to minus stupid and they aren't quite as bad as eastern Ontario on the whole.  It does get quite cold here.

I ride year round any weather, but when it starts to get sloppy on a regular basis, I switch to my cyclocross racer and kenda semi knobby tires.  I find the wet and slop really to be worse than the really cold.

BTW - nothing is more exciting to me than riding to work before the sun comes up in snowing, blowing and drifting conditions.  It really gets may heart going

I have rode comfortably with layers (basicaly every piece of cold weather bike gear I own) at freezing or above.  But the biggest problem is the slippery trails or road.  I hope to get studded tires this year, because the ice freaks me out.  I went out in March last year and fell on an icy slope - even going straight.  Tire just slid out from under me, fortunately i had all those layers on...

I 2nd the boots:   My husband rides in the winter, including on icy lakes in 0 temps and he's tried it ALL.  He loves his Lake winter boots.  A must have for winter riders around here.  But any sort of boot with platform pedals is a close second.  It's easy to get snow in your cleats. 

1 also 2nd the lobster claw gloves:  I actually like to wear mittens when it's very cold, but at least do the lobster claws so your fingers can warm each other.  Even the best gloves will get cold fast.

Added ideas:

1. ski helmet.  I have a skate helmet I plan to try, which is better than a bike helmet with no vents.  But a ski helmet is ideal. 

2.  Ski goggles can be had for $20, so totally worth the money.

3.  High-vis vest on top

4.  Carry a foil wrap/sleeping bag, like hikers use.  If you have to stop, it's brutal if you're sweaty.  I carry one on runs as well.

IMHO- I don't think riding outside is THAT important. Certainly more enjoyable but you can get away with doing the majority indoors.  

I'd say do your rides on a trainer and wait for those odd warm days that come out of nowhere and hit the outdoors just to touch up your bike handling skills.