I use a cyclo cross bike as a commuter. I have it fitted with panniers for the grocery shopping trips and I carry a back pack which is adequate for what I need at work. I swap between two sets of wheels. On wet weather days, I use 35mm tyres and on day days I use 23mm tyres. The bike I have is a Kona Jake the Snake. I bought the frame from ebay for $300 and snapped on bits and pieces from the bike shed to complete the bike. Its not flash, but get the job done. When changing over the wheels, I have to do a bit of adjustment with the brakes but once you are used to it, should not take you more than 5 to 10 mins to adjust them.