I get excited about ideas, especially the free exchange and development of ideas in the public domain. In my husband's line of work this is known as Open Source, more creative types see it in Creative Commons licensing.
Here's a few that have entered my imagination in the last few months.
Window Farming in Brooklyn, NY
This one involves vertical hydroponics in apartment windows. It's a group effort to build, experiment, and share techniques to improve window growing. Brought to us by the vigilant surfing of This Garden is Illegal's Hanna.
The second one involves the use of compost to heat homes and generate methane-based fuel to run cars. A French gentleman named Jean Pain did this in the '60s.
Link to the German documentary (w/ English subtitles) @ Pain
It comes in 2 parts and lasts @ 15 minutes. Brought to us by my husband's coworker Jim A. who was researching in that direction. If subtitles aren't your style click on the link and see the other experiments on YouTube regarding the Jean Pain method.
Within a week of Dean sending me this link I read a post on creating a compost-heated greenhouse/hoop house for worm farming or winter planting.
One Straw--winter vermiculture (worm farming outdoors in WI using compost heat)
One Straw--Rob discovers Jean Pain (and picks apart his methodology in the comments)
One Straw--end of January follow up to 2 months of work using compost for heat, worm growth, and sprouting
If you're a serious environmentalist or an intellectual gardener, I highly recommend Rob's blog. I don't always agree with him but he has the mind of engineer and is interested in real hands-on application of concepts like bio-fuel generation and sustainable farming. There are always a lot of interesting ideas floating around his blog which he is putting to work in his Wisconsin allotment. How he has the time, I don't know.
No plans, as yet, to apply either of these ideas but they intrigue me. Any new ideas where you are?