Never saw one IRL, but way back in, I think, the late 60s, early 70s, I saw a magazine ad for something called "the Franklin Bicycle" ... it was an upright configuration and had a mostly-conventional diamond frame, except that the top tube was lower, and bent up at the front to connect to the head tube, giving it a more forgiving standover height. What really set it apart was the front brake, which was a band brake. They'd had a custom rim extruded which had sort of a drum surface appended to one side of the rim, and a piece of (IIRC,) plastic pallet strapping tape forming the brake band around it. The ad raved about the superior stopping power of this. Being the sucker I was back then, I thought it was really cool, but the price was way out of my range then (thankfully).
Anybody else recall this thing?