I've been thinking about alternative energy generation lately. One reason is to eventually get off the Houston grid.
(We have power outages more frequently than we should - some due to malfunctioning equipement and some due to the fact that we have above ground lines and lots of trees. Why we don't bury our power lines is beyond me. Any initial extra costs would be recovered quickly in reduced maintenance.)
I've been particularly intrigued by Sterling engines, which generate mechanical motion (and hence can generate electricity) from differing temperatures (Stirling Engine). There is a project beginning which will use just this technology in California (Sterling Energy Systems).
The heat pump systems already used in residential settings turn the sterling engine around for cooling and heating purposes, but are based on the same principles. It seems we should be able to use a sterling engine along with a radiant heating system, similar to those used for hot water generation, to build a home electricity generator.