One of the simplest solutions is to create a user account, set its status to Available, Follow-Me, and specify the list of phone numbers that should be called. Then configure Attendant to transfer calls to this user outside of regular business hours.
The reason that this isn't so easy to setup as a queue is that this requires user accounts to be logged in and Available (not Available, Forward etc.).
The most flexible solution is, of course, a custom handler application.