I take it you don't watch tv/movies, read fiction or listen to music? What's the point in making a better society if you can't enjoy it. Stop and smell the roses ffs.

The word fissionable means something else when it comes to nuclear material.
If you're talking about isotopes that readily undergo fission from thermal neutrons (in a typical reactor), then that's fissile material.
Fissionable isotopes are ones that will undergo fission when hit with very high energy neutrons such as in thermonuclear bombs or possibly in a fast neutron reactor.
U238 is fissionable but I think that most heavy elements around and above Thorium are also fissionable.

It's opinions like these which make me want to go live in a city under the sea, and see how humanity survives without 'dull weirdos' keeping the lights on.

I feel this'd work best on a head mounted device, since it'll already be in proximity to the brain, and I wouldn't have to mutter "glass..." every time I wanted to do something. Can't you already buy this kind of technology off the shelf though? Such as Emotiv.