Apparently, someone eventually got around to making these Radio Control Racer figures of Sonic & Tails. After sitting in 'prototypes' for quite some time, and changing their look, they've finally come to market...at least at www.play.com
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They're clearly trying for a classic style, and Sonic works ok, but the Tails is a miss with a bit of big-body, small ears and a rather poor expression. The toys themselves are a bit odd too, as they are powered by and roll on the black logs that they're seeming to be 'jumping over'. The wheels in the heel and toe of the figures keep them rolling smoothly/not dragging...but the look is just ok. Fortunately the finished products (Seen left and right) improve them somewhat, by taking away the black border on Tails' eyes, moving Sonic's eyes up, bending his arm some, and making the wheels a bit better looking on both devices. 

The top two photos here should be considered as prototypes, the bottom two should be considered what you'll get if you buy, complete with final box. The product names here are "Sonic Racer" and "Tails Racer". These were seen at Argos in the UK for about 9.99 pound each. Added info by Red