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A tiny radioactive battery could keep your future phone running for 50 years
(www.techradar.com)
This is a most excellent place for technology news and articles.
He got it right in a lot of aspects, partially because he didnt gave many details about certain stuff, but I remember a pretty good description of a nuclear powered e reader... if I remember it correctly, the nuclear part was a tiny nuclear reactor though
Seemed like all the writing of that era was under the spell of nuclear power. I remember thinking "wtf?" to a nuclear-powered desk side trash incinerator in one of Asimov's books. Maybe Foundation.