http://www.delbertbao.net/2011/12/06/object-oriented-design-part-1/
http://stackoverflow.com/questions/764933/amazon-interview-question-design-an-oo-parking-lot
Design a Chess Game:
http://codereview.stackexchange.com/questions/71790/design-a-chess-game-using-object-oriented-principles/71797#71797
