The genus Bacillus contains the rod-shaped bacteria Bacillus Anthracis, the organism responsible for causing the nasty disease anthrax (as brough to your doorstep by your friendly neighbourhood islamic terrorist
Cocci are spherical in shape, streptococcus pyogenes being an example, Vibrio are corkscrew shaped, the causative organism responsible for cholera Vibrio Cholerae being and example. Trepanoeme (spelling incorrect I think, but its rough pronunciation is trep-uh-neem) are the family responsible for syphillis (trepaneoma pallidum I think), the ulcerative tropical disease yaws, and a few other particularly obnoxious ailments, often marking bone quite severely, and causing some very severe progressive slow incubating illnesses are sort of wiggly shaped, like tiny little worms under a powerful microscope.