What's your favourite thing about commuting by bike. For me it has to be skipping past huge traffic jams in seconds that could take hours to negotiate by car. That is such a thrill for me. I also like arriving fresh (spring, autumn and winter at least, its a different story in summer) at work/ school and seeing everyone pouring of a seriously cramped train or bus.
Lastly, having the journey in your own hands, unlike any other method of transport, your totally independent of other factors. Admittedly seriously dense jams can slow you down but most of the time, journeys take as long as they should and arent dependent on train delays, traffic jams etc.
What about you guys?