This year 2012, I improved the dripper tracker for low tech solar tracking, did the lean away greenhouse (it won something on instructables) and started "pallet gardening". Pallet gardening is going really well. I also did dripper irrigation, (just started) and it seems to be working nicely too. I hope to get the low tech solar in demonstration mode pretty soon.
I am 49, live in victoria BC and work as a stonemason.
I have several simple 3rd world help projects. My pulser pump which uses water power to pump water is now in wikipedia. (I am not allowed to touch the page but I don't think it explains it properly).
Pulser pumps have no moving parts and are not ram pumps.
They can use large volumes of low grade water power.
I also made the "mechanical mathematician" which is a simple device to form a decent parabola for solar ovens. It can be used directly to form the parabola with no knowelege of mathematics. I expected the mathematician to be used widely in the next couple of years. I made the first one in late august 2007.
I also made the solar design T-square and clam shaped reflectors for unattended solar cooking.
And the dripper tracker class of solar trackers.
Currently I do a little work on the nano airlift pump concept. This is the idea of using very low pressure (about 2 psi or less) to pump water with small tubes and the airlift pump method. The best I got so far was 18 ft high with about 1.5 psi.
Unfortunately nobody takes any of this seriously and so far none of the above things has been independently tested.