Had my first flat while commuting the other day in 16 months of bike commuting. I've had a couple of other flats during that time that were slow leaks that happened while my bike was sitting in the garage overnight, but never during a ride.

Decided to drive today because I was really dragging on my commute yesterday. I had ridden 8 out of the past 9 days and my legs were feeling tired and my energy levels low. It's also been very hot and humid, so I guess my body just needs some recovery time. Good excuse to go kayaking tonight after work! I've started paddling this summer, and it seems to be the perfect recovery exercise. It gets my heart rate up, but uses a very different set of muscles than cycling. It's also a very pleasant thing to do on a hot summer day.