I'd say of all the robotic Sonics, my favorite is definitely Mecha Sonic from Sonic 2. What's yours? (and yes, the rolly dude from Spring Yard Zone does count, as far as I'm concerned.)
Hmm, cycled several songs in my playlist, so maybe I'll just put them here instead of in the box..
Currently listening to:
Sky Chase Zone (Late Remix) [midi]
Chemical Plant Zone (Chemical Spill Metal Remix) [midi]
Death Egg Zone (Legends Remix) [midi]
Emerald Hill Zone (Gospel Choir Remix) [midi]