Berg, do a google search for Piper Precision Products Vulcan Cannon M-134A1, 120bb/sec. 5" grouping at 50', 8" at 100'
They start at about $2500/usd, $5000/usd with the predator style backpack set up.
http://www.myspace.com/video/vid/533523
Now thats the one I want
My newest aquisition, was not in my other photo. Picked this one up recently, locked it out to semi auto only, shoots just under 475fps.