I recently bought the excellent Humble Indie Bundle 9 and was delighted to see Dear Esther included.
I played Dear Esther when it first came out last year, in a dark room, with several beers through the night in one big greedy sitting. It's a beautiful, intriguing, captivating "game" that has no real gaming mechanics to speak of. It's a story, a journey through a beautiful landscape.
It is difficult to recommend to those who's only gaming is spent attempting to prestige for the 60th time -- and there's nothing wrong with that! However; for anybody looking for something a little different and a journey that you'll not soon forget I highly recommend checking this out.