The little rocket stove that could.
Building a Repurposed Windows Greenhouse ~ you can make a greenhouse inexpensively using old windows! http://ourfairfieldhomeandgarden.com/building-a-repurposed-windows-greenhouse/
solar tube bend
rammed earth construction techniques | Green Home Building: Naturtal Building Techniques: Rammed Earth
DIY Solar Pool Heater - Rob A's (Im)personal Blog.
7 Solar Water Heating System Designs
The Oil Drum: Campfire | Practical Passive Solar Renovation - Part 1: Easy First Project
Solar Box Heater - http://www.ecosnippets.com/alternative-energy/solar-box-heater/
Solar panels. I have long thought that solar panels need to look like regular tiles to really take off. Till then, this combination looks fantastic!!!
Larkin's thermosyphon solar air heater