Pearl Izumi X-Alp Seeks are supremely comfortable on and off the bike, and don't scream "bicycle shoes!" when off the bike. I used them a lot in Seattle when going form home to childrens hospital because i could just unclip, lock the bike up, and walk right in...

The cool thing about these is that they make a running shoe that uses the exact same top, so they look rather normal--and the cleats ride up deep enough that they are mostly quiet when walking (on certain tile floors they would click).