[Dr. Drib]

I say we go for four! (Not that there's anything wrong with that!)

Why? Well, why not! After all, we already have these:

1. The four Beatles
   
2. The four Ghostbusters
   
3. The four kids from South Park
   
4. The Golden Girls
   
5. The A-Team
   
6. The Marauders (from the Harry Potter books)
   
7. The G4 nations
   
8. Four blood groups
   
9. Four types of teeth (in humans/primates)
   
10. Faces on Mt. Rushmore
    
11. The Four Seasons
    
12. Four letters that, properly arranged, are taboo here!