By using a particular master password and generator pattern on a username, service name, or whatnot, PassGen produces a reasonably secure pw that you can reconstruct if necessary (if you input the same parameters again). You get to select the level of complexity/security. As a sysadmin, this easy-to-use tool lets me assign passwords that are possible for users to remember (there is always a mnemonic element to them) and more secure than people tend to select on their own. This system also makes it possible for more than one admin (by using the same master password, pattern, and method for selecting the base name) to generate or reconstruct consistent passwords.

Passenger is another useful tool by the same author that incorporates the same password scheme for managing user accounts on servers.