I agree with Monster Pete. Both my wife and I have pretty nice bikes for "real" rides, but we commute/shop/hang out on two old steel mountain bikes. I bought my Bridgestone MB-3 new about 20 years ago, but her Specialized Hard Rock came from a thrift shop for $25--WITH a $40 Blackburn rack and Cateye computer. Where I live you can find rigid mountain bikes--Diamondback, Bridgestone, Specialized, a few others--for $40 or so in places like Good Will or the salvation Army, and many have barely been ridden. They're sturdy, fast enough (a change of tires helps), fun to ride and not particularly attractive to thieves.