| "The Football" is a codename used by the US Secret Service. Wherever the President goes, there is an agent somewhere nearby with what looks like an ordinary briefcase handcuffed to his wrist. This case is what's known as "the football". Details about this case are highly classified, although it is fairly well-known that it contains nuclear launch codes, and probably some kind of satellite communications device, by which Armageddon can be unleashed from wherever the President happens to be.
A good movie about this device is "Chain of Command", which stars Roy Schieder as the President. Also, for more information if you're fascinated by this kind of thing, The Custodian has an excellent writeup under nuclear launch codes. See also: "The Briefcase" | 
