one of the guys i ride with uses the Italian Bike Mirror, that someone else posted the link to, and he loves it. i was actually going to pick one up this week, on e-bay, considering the inexpensive price and easy install.

http://search.ebay.com/search/search...AD+BIKE+MIRROR

the LBS by me sells the larger one, which is 2 pieces, and much larger. they also recommended the Italian one though, over the one they sell, and they said it was much better too...