Sudo Login (or Masquerade) allows Administrators to log in as any regular user without asking for their password and without disconnecting them. Specially useful for configuring their workspace (filters, reports, dashboard) or to support users (reproduce issues, help them step by step, etc).
Other add-ons of interest
Glances - Integrate All Your Applications
Accomplish More Every Day. Spend your time on getting things done, not on finding information. Glances securely connects all of your apps and provides a simplified view of the data you need right when you need it, in real time.
Prevent Concurrent Login
Add an additional layer of security by allowing only one person to log in as a user at a time. Prevent multiple users from using the same credentials at the same time. The user previously logged in will be logged out automatically and be prompted with a message.