ICFP Programming Contest
Ninth annual ICFP Programming Contest (2006)
It was held July 21 to 24, 2006. Friday 12:00 noon (EDT) -- Monday 12:00 noon (EDT). See a clock showing EDT (Eastern Daylight Time) here (New York).
See its official homepage, too: ICFP Programming Contest. The contest task materials are available for download.
Some of the implementations (made by the participants) are also available, browse the discussion mailing list.