After commuting last winter via bicycle, I decided I'd buy a mirror for this winter. What mirror do you use?
Not that drivers don't get close in summer, winter is different. It's darker, roads can be narrower, and it may be necessary to take more of the lane if there is fresh snow.
Peter White generally seems to know what he is talking about... http://www.peterwhitecycles.com/mirrors.asp I may get one of those.
I like the cycleaware reflex mirror. Sold at most LBS.
I saw your post today. I am a fanatic about wearing mirrors and I strongly prefer an eyeglass mirror because you don’t lose sight if you stand up to climb, and I think it is easier to spot, especially in emergency circumstances. BTW, I wear eyeglasses anyways.
That being said, if you decide to wear goggles for winter riding, placement of an eyeglass mirror can be problematic. if you are interested, see a recent post of mine about how I solved the problem.