Having completed the same route/commute thousands of times, I find that different geometries really help relieve the boredom of the same bike. Early and late season I tend to prefer the tourer (fenders, rack) or sport geometry, then during long summer I migrate toward the racing geometry commuters. Depends on mood, weather etc but do appreciate the different style bikes, tire widths, etc. Last season I found for the standard river commute that fixed gear was a welcome addition as well and brings in a whole new feel on days you ride freewheels or climb hills.