Also (lol spamming the thread) Check out Eversion, another horror game with a reeeeaaallly wierd twist. It's a happy 2d platformer....Yet it's still incredibly eerie...It's available for purchase on steam where you get better soundtrack, graphics and levels but the freeware version is still great.
http://zarat.us/tra/offline-games/eversion.html
http://zarat.us/tra/offline-games/eversion.html