I have an idea for an alternate attachment, although it requires a bit of thread necromancy on my part.
It involves taking a combine harvester apart and putting the business end on front, and pointing the spitter either behind you or to your side, with whatever doesn't get chewed up flung into the air.
I think someone once said that watching the bodies and gibs of your former comrades fly at you has a significant effect on morale.
Maybe pull this attachment in when you've one hell of a human-occupied landfill to clean up, and a cleaning crew behind you. Windscreen wipers optional.
Maybe agricultural planets have a chance against invaders with this thing.
(( Shamelessly got the idea from
http://www.youtube.com/watch?v=d2eSP3D0s0w when I was drunk. ))