The Ageless, Faceless, Gender Neutral Culturally Ambiguous Adventure Person, or AFGNCAAP, is the hero of the Zork series of text (and later Point & Click) adventures.
In fact, the term is a label that can be applied to many characters, including several Zork heroes, the Stranger from the Myst series or the Hacker from System Shock. As the name implies, it refers to a character about whom we know absolutely nothing- we never see them, we don't know where they're from, how old they are, or even whether they're male or female. They are merely a shell that the player can move around the game world in their place.
Following Gordon Freeman's victory, it was decided that apparently being nothing but some artwork and an excuse to be in a lab was still too much of a character to guarantee perennial defeat, and the AFGNCAAP was suggested as the ultimate non-character. Expect severe rallying come the next character contest.