Ghost said:

Can you think of any good movies off the top of your head with no main character?

Off the top of my head:

- Seven Samurai

- the first 2/3rds of Alien (until Ripley was the only one left)

- Pulp Fiction

- Terminator 2 was always a bit questionable for me (although I suppose you could argue that John was central to the story, I never really saw him as the main/central character)

- Dawn of the Dead (the original 1978 film - not the 2004 remake)