[adamnemecek]

There were a couple of IAMA's on reddit with some teenagers who (supposedly) build nuclear reactors

http://www.reddit.com/r/IAmA/comments/hmn56/iama_teenager_wh...

http://www.reddit.com/r/IAmA/comments/xd19t/iama_an_incoming...

[russellsprouts]

These are impressive, but they aren't fission reactors, but fusion reactors. They do not generate power, but they do convert hydrogen to helium.