Donald Knuth (age 70) is considered one of the "fathers" of Open Source.

Knuth's primary system is a laptop running Ubuntu that never
connects to the Internet.

Knuth has been working on the "Art of Computing Programming"
since 1962.   Volume 4, Fascicle 0 was released earlier this month.*

*Interview with Donald Knuth...
http://www.informit.com/articles/article.aspx?p=1193856

[side-bar] Knuth's collection of diamond signs is impressive.
http://sunburn.stanford.edu/~uno/diamondsigns/diam.html
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