Ask HN: What's the best way to manage passwords within a small company?

We're a small dev and design firm of 10 people. Currently, we manage our passwords in the worst way possible - we have a single document that everyone has access to, which has all of the logins for the various 3rd-party websites and services that we have accounts for. Obviously, we're looking for a better way to do this that is more secure/partitioned, yet manageable.

Any tools or methods that I should know about?