As I'm working on my horizontal spinner 'bot, I need something upon which to test its weapon, something with a size and weight approximating my soon-to-be-opponents. So, a half-hour or so of work plus some left-overs from other projects and GENTLEMEN BEHOLD! A training dummy, complete with foam wheels (ruined by fighting). The axles are locked (more or less) to simulate an opponent who really doesn't want to be pushed around.
Appropriately named "Redshirt".