I really get excited by ideas, especially ideas that open new possibilities and improve our relationship with the environment.
That's why I perked up when I saw this article from TreeHugger. It shows how an old, 420-square-foot apartment can be renovated to maximize space and minimize environmental impact. These kinds of ideas introduce new (and, in some cases, old) ways of living that focus on what is truly needed. Also, for me, they spark additional ideas.
Not many things are quite as energizing as when people move away from talking about what can't be done and start discussing what is possible.