This beautifully-designed set of cards is a kind of dérive assistant that enables players to uncover and intervene upon the psychogeography of the cities they live in. Originally designed by Julian Bleecker and Dawn Lozzi for Conflux 2008.

The Drift Deck (Analog Edition) is an algorithmic puzzle game used to navigate city streets. A deck of cards is used as instructions that guide you as you drift about the city. Each card contains an object or situation, followed by a simple action. For example, a situation might be — you see a fire hydrant, or you come across a pigeon lady. The action is meant to be performed when the object is seen, or when you come across the described situation. For example — take a photograph, or make the next right turn. The cards also contain writerly extras, quotes and inspired words meant to supplement your wandering about the city. (Near Future Laboratory)

More info and ongoing developments: http://www.driftdeck.com/