Chimpo
From Sonic Retro
Chimpo is a guy who can draw very well; in fact, several people have been asking him for custom sprites or custom art. With that given, it's not a surprise that Chimpo is a strong supporter of the now-gone Talent Exchange forum, where he could trade his works of art with music or ASM code.
Street Fury
Chimpo Q!
He is also active as an hacker. His primary and best work is certainly Atomic Sonic, but he is also known for other hacks like Chimpo Q! and the semi-serious Street Fury. He wrote a detailed guide about SonMapEd, which is hosted here on the wiki.
See Also
On the forums
Atomic SonicStreet Fury
Chimpo Q!