I'm half asleep so I don't expect this to be too good...
Hmm, what about a stick man running possibly looking like he's screaming with an army (an army could be as little as three)of stiff looking (i guess robotic would be a good term) copies of him chasing after him? If you wanted words with it you could say "Illegal copies are never a good thing"
Another idea is having someone bending over to the left getting some paper out of the printer and while they are doing that the picture on the computer that they are printing out (ie. the copy) has bitten them in the bum. You could use anything in the picture. It could end up quite funny! "Piracy will always bite you in the butt"
That's a toughie there..I don't think you can positively get rid of the people who want to steal your work. If you're looking for a design, the more complicated and recognizable it is, probably the less it'll be stolen. If they try to get rid of the logo, it might be harder to do if it's really intricate or complicated. And, if they don't even get rid of it, then someone might recognize the logo and report them.
what about a logo showing mal-functioning and litle different (i.e. different coloers) versions of known things, inside a banned circle? like a Mario named Malio, with different cap, or a Tails wit h3 tails instead of 2, not being able to fly, or an Arnold as plastic Terminator who, instead of shooting enemies, shows an error screen and shuts down himself XD or any other random thing like this.
this would just show that, even if being similar, illegal copies are never perfect =3