Vault Turret Terminal Password
It can be found in the Sierra Madre Vault in the room with the 3 holograms on the lower catwalk.
Don't use this unless strictly necessary.
The Vault is off-limits. There is no reason to enter it unless your clearance is personally approved by Mr. Sinclair.
Still, if anything were to go wrong with those security systems, use this password in the Turret-Defense terminal inside the Vault's Chamber:
M&M Construction Inc.