Internal combustion engines that run on water? Over-unity generators? Mid-road wind turbines to harvest the wind energy of passing cars? Anti-gravity? (and these are just the ones that got past the moderators!).

Of course, there are more serious contributions. Energy and sustainability have a strong presence. The enthusiasm for space exploration continues unabated, whether it’s just for the blue sky fun, or for the rather more serious goal of species preservation.

There are also many comments dealing with the increasing difficulty of technical engineering and the need for improved methods of collaboration. One chap suggested a website in the MS Project style for the management of an energy independence plan for the USA. Another suggestion was connecting all our brains into a “Mind Matrix”.

It was interesting to see how many of the comments directed at improving energy infrastructure or third-world technology were motivated by either guilt at the negative perception of the USA or the need to isolate the USA from dependence on foreign oil.

And of course, the number of people registering an interest in immortality and 3D television was fairly high. Presumably, the 3D television is to give you something interesting to watch for all eternity.