Admin interface ideas

i am working on a base rails app that i will use as a starting point
for a few projects.

i am using restful_authentication with aasm and role_requirement. the
work flow for users to sign up, activate their account, edit their
info, change and reset passwords all works great.

i am about to start setting up an admin area to manage the users
(create, edit, suspend, activate, delete, purge, etc) and some other
site settings. has anyone come across interfaces that they loved? i
want to look around at some examples before i start. i don’t care if
they are coded in ruby, php or whatever.