maybe start commuting on a soft full suspension mountain bike with big fat knobby tires, that will add some perceived miles
i like changing up my route quite a bit, if im in a hurry i have a pretty direct route but if i feel like going for a ride there's 3 or 4 bike paths i can incorporate. that's part of the fun of a commute by bike, you're going to/from work, but you're also going for a bike ride.