Watch your feet everybody! Runaway brain coming through!
Drawn in Photoshop on the graphic tablet.
Here's the original sketch. I like the looseness of the sketch, and tried to preserve that in the final drawing, however, his pose is all wrong here. The guy's all bent over, when his entire body should be leaning forward as if he's running at top speed.
Here's the second sketch. His running pose is better here, conveying movement and speed. I'm not sure what that tail trailing behind the brain is supposed to be. A spinal cord? Nerves? I don't know. I ended up deleting the tail in the final drawing.