This is my take on a live action Sonic. I know its probably not what most people are looking for, because its a departure from the cartoon design in a lot of ways. I just thought people might find it to be an interesting perspective. If Sonic were done in a more Rocket Raccoon-esque way, using bits of real hedgehog anatomy, while trying to maintain the personality and appeal of the cartoon. I don't know if I was entirely successful, but its just a quick proof of concept and not a full movie ready creature design (especially considering the the hair is just sculpted on and not true cg hairs and quills).
A few quick notes about the design:
1. I am not a huge fan of the modern Sonic design, I greatly prefer classic Sonic, before his limbs got stretched out and when he was still round and cute like a cartoon hedgehog. I think real hedgehogs can be quite cute.
2. This is before he acquires his classic red shoes in the second act. I think he could look good with some realistic sneakers, if they were proportioned right.
3. He looks a bit strange from the front view because he is still perfectly symmetrical. Some asymmetry would be needed in a final design to look natural.
4. Finally, I think Sonic and his world better lend themselves to an animated film in a Pixar-type style. This is if you HAD to make a realistic Sonic, which I saw as an interesting design challenge. I personally don't like cartoony/stylized designs coexisting with live action in movies unless its a key plot point like in "Who Framed Roger Rabbit." That is why I chose to make him a little more like a real animal.