This happened a few weeks ago, when I was train/bike commuting. I got off my train at Waterloo Station, unfolded my bike, cycled towards South Bank with the Bromptons, Dahons and a Strida. Probably there was Ridgeback, too. While waiting for the lights to change, this really weird looking bike went by. The wheels were HUUUGE and the geometry was all wrong. The rider looked so vulnerable perched up there.
Yup, it was a road bike. My reaction was just as strong as my double take was the first time I saw a Brompton go by.