[edj]

The only website he lists that seems irreplaceable to me is Wikipedia.

Everything from source discovery, to unearthing basic facts, to hypertextual excursions through human knowledge is so much easier and more fruitful now, it's hard to imagine going back to the way things were before.

[lmm]

I don't think I've used wikipedia in the past three years.

Life would be a lot worse without my Kindle, but in terms of a website that changes the world in itself, I can only think of arXiV. I remember what trying to look up actual research papers as a high school student was like before it.