This reminded me that notch web game[1]. Both kept me interested and I find them a very pleasant form of art. [1] http://game.notch.net/drowning/
Surprised no one has mentioned Cookie Clicker yet, which I think was what inspired notch to write that game: http://orteil.dashnet.org/cookieclicker/ Notch's game was written in Dart and the source code is simple and elegant: http://ludumdare.com/compo/ludum-dare-29/?action=preview&uid...
Game.ClickCookie(null, 100);
Gives you 100 cookies.There is no limit to the number you can input.