SegaDriven pointed out this excellent custom made Sonic mech figure that an Etsy seller named KodykoalaToys made. Inside the head of the Sonic mech figure is another Sonic figure behind the controls. Neat!

The custom figure was made from an 8 inch tall vinyl figure that is fully articulate, with the smaller Sonic being made from a 2 inch figure. He is asking $275 for this one-of-a-kind Sonic figure.