The Mars Global Surveyor is expected to arrive in orbit around Mars in September of 1997. Its goal is to do a high-resolution mapping of the surface of Mars. Mapping should last from March 1998 till January 2000. One of the features in the target database is called the "Face on Mars" (in the Cydonia Region, at approximately latitude 41 degrees North, longitude 9 West), claimed by Richard Hoagland and others to be an artificial construction. This claim will pay out $1 per YES coupon if a high-resolution image of this feature is released before 2001/1/1, $0 otherwise. It is irrelevant whether the feature is really artificial or not.
Apart from possible failure of the spacecraft (as happened to the Mars Observer in 1993), it is possible that the Surveyor will not get a picture of the Face itself, due to uncertainty of its position (see http://barsoom.msss.com/education/facepage/face_discussion.html). Additionally, conspiracy theories abound, suggesting that NASA won't release high resolution pictures of the Face even if such pictures were taken.
In order for this claim to be satisfied, a picture will have to be released showing at least the "nose" of the Face, with a resolution better than 20 meters per pixel. The current best resolution picture is 43 m/pixel, the Surveyor is capable of imaging at 1.4 m/pixel, but may be doing a 8X averaging (12 m/pixel) to save memory and cover a larger area. The picture will have to be acknowledged by NASA as genuine.
For more information, see:
http://www.jpl.nasa.gov/mgs/home.html or http://mgs-www.jpl.nasa.gov/ http://barsoom.msss.com/education/facepage/face_discussion.html http://barsoom.msss.com/education/facepage/face.html http://www.cityscape.co.uk/users/iy12/aaes/mars.htm http://www.planetarymysteries.com/marswatch.html