A friend of mine teaches raw food "uncooking" classes and I thought that some bicycle powered appliances might be a good addition to his repetoir.
+) bicycle powered blender - mobile
+) bicycle powered food processor - stationary
+)a passive solar dehydrator might be good for preserving fruit from his cherry and pear trees and other fruit gleaned via http://www.urbanedibles.com/
I run a gallery and grassroots hub in Old Town Chinatown, called SEA Change. SEA = Social Environmental Art. As a physical symbol of this mission, I'd like to add some homemade solar panels or windturbines to the roof:
+) solar panel from broken solar cells
+) solar panel diy
+) wind turbine from old scanner - I bet Free Geek has free broken scanners
I'd also like to build some planters for the inside. Since the gallery is downtown, the air is pretty polluted. Some native ferns and other air cleaning plants could do wonders for my health and make the gallery more inviting:
+) Zach also suggested building wood planter boxes and water catchment trays lines with trash bags.
+) Living walls could be another cool option:
Change the system, not the climate!