I have a flat bar road bike for my 7.5 mile commute. I love it. Speedy like a roadbike, but with a heads-up riding position for in the city. I put bar ends on it and I've got multiple had positions. Some options I can think of would be the Jamis Coda, the Novara Big Buzz. My bike is unfortunately no longer being made (a Felt SR81).

If you like drop bars, a Trek Portland is pretty sweet. Compare to a Jamis Aurora, I believe.