From the introduction:
Sleepers is a "choose-your-own-adventure" style game played on a wiki. In it, you will explore The Dream (or is it The Dream?) where you woke up, trying to survive and, perhaps, learn the secrets of this place where you finds yourself. At the same time, you will be creating new areas of The Dream for other players who will play on the same wiki.
User summary:
The game is played as a solitaire excursion. However, the game play is recorded in a shared wiki, where the play logs and artifacts can be used by other players. In this way, the game is an intriguing fusion of solitaire and non-solitaire play. The game is published as a four-page ODT document, although the first page is entirely blank.
The game does not feature an established shared wiki; player(s) would need to establish this prior to play.