PHX, outside of rush hour, I could leave home or office 45 minutes before a Southwest flight, maybe less if I had a ride. Las Vegas is about the same. But I don't cut it this close. I usually allow 90 minutes, and try and get a decent seat.

An older biography of Bill Gates called "Hard Drive" talks about his early-days hobby of seeing how close he could cut it. It sounds like having a Porsche helped...