Tried/Liked:
1) Montague Folding Bike (I have the single speed Boston model) - it rides like a non-folding bike, but if I want to take the bus home, I can fold the bike and take it on with me, without having to worry if the bus has space in the bike rack that day (especially on days when it rains unexpectedly, and I and so many other commuters did not take my rain gear)

2) Speaking of rain gear, shoe covers. It is thanks to these that I did not need to carry an extra pair of socks with me every time it was raining in the morning.