RE: Name that doodad, greeble, keg of beer, or whatever.

How about:

The Mk IIIA bio-organic refuse recycling unit.

In an attempt to allow lower tech mechanized units more freedom of
movement 
away from logistical units, a third generation Organic-Mechanical
Processing 
Accessory (OMPA) unit was attached to units for extended operations. 
The unit 
digests and processes organic matter and extrudes compact bricks of
organic 
material suitable for burning in high-efficiency furnaces. This allowed
the 
crew to fuel their vehicle from local sources.	A by-product of the
process is 
water, which is commonly used as a working fluid to drive the power
turbines of 
the vehicle.  Initially installed in the interior of the vehicle, crews 
objected to the noise and smell of the unit which was then installed on
an 
external mount.  Due to power plant ventilation requirements, the units
was 
mounted on the front of the vehicle to keep the vents clear.

--Binhan