Images: A world without oil

A new alternate-reality game called World Without Oil will ask people to envision--through characters who are blogging and writing stories--a world in which the United States has been cut off from oil imports. Then visitors will be urged to participate in the game by writing their own stories, creating videos or even conjuring so-called flash mobs in U.S. cities.

The game, which is funded by PBS, will launch April 30.

Photo by Worldwithoutoil.org