Stamp - a token that postal fees have been paid
Letter - a written message addressed to a person or organization
Santa - Santa Claus
Server - (computing) a computer or program that supplies data or resources to other machines on a network
To crash - (of a computer system or program) to fail suddenly and completely because of a malfunction
Gee (interj.) - used as a mild expletive or exclamation, as of surprise, enthusiasm, or sympathy.
To guess - to make an estimate or conjecture