OfPhailure: Better than most sets out there, but..yeah. Rates a meh. But like BenDover says, Robothingeh stands out.
ashaltaf: Simple and sweet always works :P Kinda reminds me of Hampa and Chez combined. Trails look so out of place, lol. Maybe two big arrow-lines would be enough. And the head doesn't necessarily have to have 'eyes' and/or 'mouths'.
On another note: (I'm bored)
Yay! Fulfilled 15k head request by Alessandro :P I'm so lucky BenDover didn't notice the topic, otherwise I'd be utterly pwned.
Ooo, and my entry for ROBO-Mohawk's ground texture request (don't any one of you try and interfere D:<)