In this eBay auction for a 77 Schwinn Caliente a freewheeling chainwheel is described:
"The Schwinn Caliente is unique in that it has a front freewheel gear system. This means the chain continues to rotate around when you stop pedalling and was designed to make it easier to learn to ride a bike - you did not have to pedal in order to switch gears."
Apparently, instead of the rear hub freewheeling, the front sprockets do, so that shifting can occur without pedaling. I'm guessing the bike still needs to be rolling, which makes it a lot less useful. Shifting while stopped wouldn't work.
Anyone seen these before?