This article just make me sick. Any discourse involving slums without considering the effects of poverty just comes out wrong. Of course people living in slums " have minimum energy and material use". They have to. They have no choice. With such a small amount of resources that the people in the slums have they are forced to use them as efficient as possible. Something we, wealthy people, don't need to. At least in our own narrow perspective. We, the rich, aren't less energy efficient because we happen to live less dense. It because we feel like we can afford it. I can go by car, not because it's the only means of traveling, but it's more convenient and it doesn't mean I have to refrain from eating a couple of days. A enormous amount of the worlds population don't have this luxury. One proof of this missintepration of why people in densely populated areas are more energy efficient is that rich people in, for example, Manhattan (as it is used in the article) will most likely travel a lot by taxi and several times a year, if not monthly, travel by air. The reason for this: because they have the resources to do so. It seems like we're benign to use whatever resources that are available to us. I don't want force everyone to live like those in Rosinha, Rio de Janeiro. Neither do I want everyone to put a strain on the world like the financial elite. Judging by the growth of the world population and the state of the environment, we, rich and lucky, need to learn to use what we have in a much sustainable and efficient manner. We might have to look to the poor for this knowledge, but don't think that they are more efficient for no other reason then a dire need to be so.

I'm a Gentoo user. I don't use Gentoo primary to learn things. Of course you do learn some stuff if you get your hands dirty, but that's true for all distributions. The advantage of Gentoo is compilation for a particular machine, but doing it the easy-peasy way.

Learning things I did when I failed a Linux from Scratch installtion three times.