Well, Canon did offer a remote battery accessory for the A-1, I'm pretty sure. And since the New F-1 takes the same battery, that accessory probably works for the F-1 as well.
Speaking of other cameras that use the same battery, the Nikon EL 2 (and probably the Nikkormat EL), Bronikca ECTL (I think?), Bronica ETR-series, Pentax 67, and no doubt others.
Unfortunately, these are all film cameras.And I own five film cameras that take this battery. It used to be a common one found just about anywhere. Nowadays I'm having no luck finding this battery on the racks of any of the local stores that carry a variety of batteries, including those allegedly for cameras. I guess I'll have to either buy off the internet or go to Batteries Unlimited and pay too much for it.