Go to
this page and try the Sonic Character Creator. Then, take a screenshot and post your creations here. Some rules, though:
1. No more than 3 per post. EVER.
2. Don't make the same thing as someone else did, or worse, steal their pic.
3. Don't flame anyone because their character doesn't look good.
Other than that, you're pretty much free to do whatever you want. Here's my examples:
Sonic, so no one else does it first:
My fan character, Thunder the Possum:
Some human kid:
Let's see if you can do better.