The early Fuji FinePix DSLRs(S1, S2, S3) had a 4x AA tray, but were supplied with NiMHs and a charger. I actually kind of like that set-up as you can still use them today without hunting down proprietary batteries, but even fresh NiMHs don't last super long. The S1 and S2 were extra fun as they still needed two CR123A batteries in the grip to power the "camera" functions(Metering, AF, shutter timing, mirror operatoin, etc) while the AAs power the "digital" part. These cameras are Nikon film bodies, the N65 for the S1 and the N80 for the S2 and S3, with a Fuji sensor and electronics stuffed into a fattened-up body. And yes, they're clunky(the S5, which is built on a Nikon D200 body, was and IMO still is an excellent camera).
The battery grip for the Nikon D200/S5 is really meant to hold two EN-EL3a batteries(or their Fuji equivalent if using the S5-the S5 will power up with Nikon batteries but refuse to operate even though they're electrically the same and use the same charger) but can be powered from a 6 cell AA tray. The last time I tried it, I got about 25 shots on fresh Duracell alkalines.
Most of the higher end AF era film cameras ran on AAs. Older pro class manual focus high speed cameras could use almost comical numbers of AAs. 8 is a relatively common number on those-offhand the MD-2/MD-3 for the Nikon F2, the Motor Drive FN for the Canon New F-1, and the Nikon F5 all used 8 cells. The Nikon F4 can be configured for 4, 6, or 8, but the 6 cell configuration is most common in the US(I like the 4 cell one, but it took me a bit of hunting to find one). IIRC, the motor for the Nikon F3 uses 10 cells. The F6 dropped to 2x CR123s unless you use a battery grip.