[Retric]

About 1/3 of the worlds population would be happy with 3$ / day. In the US it's reasonable to live on rent + utilities + transportation + 10$/day. However, most tech people pass this so quickly it's not obvious.

Anyway, I am 27 and make twice what I did at my first post collage job and I still spend most of what I make. Back in collage a friend of mine went to school full time made ~10$ /hour and supported his wife and kid on that. I think he was happier then than I am now because he was going to make it to a better place. It's easy to assume you need have some life style to be happy but I think a reason for living is far more important than your income or your wealth.