Food Poisoning Differential

Vomiting Predominant: 

Staph aureus (esp. mayo)
Bacillus cereus (esp. rice)
Noroviruses, eg Norwalk

Watery diarrhea predom:

C. perfringens
Enterotoxic E. coli
Enteric viruses
Cryptosporidium
Cyclospora
Intestinal tapeworms

Inflammatory diarrhea predominant

Salmonella (typhi and non-typhi)
Campylobacter
Shiga-toxin producing E. coli
Shigella
Enterobacter
Vibrio (usually parahaemolyticus)
Yersinia

Non-GI Symptoms

Botulism (descending paralysis)
Ciguatera toxin (paresthesia)
Scombroid (flushing, itching)
Listeria (meningitis)
V. vulnificus (cellulitis, sepsis)
Hep A (jaundice)
Brucellosis (fever, arthralgia)