[analog31]

Shimano Front Freewheel System (FFS) for a while in the 1980s. The only bike I know of that had one was the Schwinn World Tourist. I only know about it because I found a World Tourist in the trash and rode it for many years but with a different drivetrain.

[prmoustache]

There are other more modern systems with a crank mounted freewheel for enduro and DH bikes, allowing the rider to change gear while coasting in anticipation of a pedaling section. Similar to gearboxes, the idea comes back once in a while but never really takes off massively.

There was a french company named HXR components which used to produce that, I think they went bankrupt. Nowadays there is the Rocksteady Magic from boutique euro brand Intend: https://www.intend-bc.com/products/rocksteady-magic/