E-brake disk on driveshaft?

[mudmizer]

Might be an odd ball set-up but has anyone ever thought about some kind of E-brake rotor mounted to the drive train like some of the older big truck drum set ups on the rear of the tranny? I installed rotors on the rear of my 14 bolt and have flerted with the idea of installing a small disk brake rotor at the yoke and using the pinion mounting bolts to mount a caliper to. I figure the hardest part would be getting the roter true and ballanced.

Anyone ever tried it? seen it? have a picture?

I know I should just get the E-brake calipers for the axles but thought this would be a fun project. Like I don't have enough things that I NEED to do.