We made it a point to stop at Mezcalitos on our drive around Cozumel because we were referred there for the shrimp by some friends. The shrimp did not disappoint. This restaurant and bar is located as far north as you can drive on the east coast, right where the road cuts back west to San Miguel. Definitely give this place a visit, and be sure ask for a paint pen to write your names on the walls.
Here are some photos from January 2011: