My very first commute was last year and all year I commuted on a 700c converted mountain bike with drop bars. Bike serves me well, but apparently the city I commute through has no money to fix potholes. My very first commute this year resulted in a flat from a huge pothole. Got a ride home. Second commute and got another flat from a different pothole. After that I built a 26'er Cruiser single speed with 26x2.125 tires. My commute is mostly flat so I don't need gears. Bicycle commuting is different from my weekend rides and don't even use a computer to log miles. My commutes this year have been much slower, but I don't care.
No matter how crappy my day was at work, everything is forgotten the minute I jump on my bike and head home. This is the beast I build for the poor roads........
Today is was a chilly 44 degrees and cloudy, but by time I left work it was 55 degrees and sunny. Well worth it like every time.