GAME: Judith (Increpare & Distractionware) 2009

Title: Judith (win, OSX, source, linux) 
Authors:  
Terry Cavanagh  http://www.distractionware.com           
Stephen Lavelle  http://www.increpare.com
Year: 2009
Region: Ireland

GAME: Foldit beta (Center for Game Science at University of Washington) 2008

Title: Foldit beta  (download for Win, Linux or Mac)
Author: Center for Game Science at University of Washington in collaboration with UW Department of Biochemistry
Year: 2008

Region:USA

The players from this game solved a complex biological problem (somehow related to HIV).

See this article published on Sept. 18 2011: 

Crystal structure of a monomeric retroviral protease solved by protein folding game players