Having a big picture idea of what is happening in any field is very wothwhile while thinking about problems, solutions and opportunities.
If you start looking for some ideas, VCs may be a good guide to this. They need to invest across the whole sector, guess the potential of various ideas and have a general idea of where things are.
A while back I wrote about the investments of Vinod Khosla in Energy. One great learning was the way he organized his entire investments in energy into various parts.
Now, BNET (a sister company of the successful tech publication CNET) has a Green Tech 101 video presentation from Adam Grosser, general partner of Foundation Capital. The beauty of this 5 minute video is the way he has organized the entire sector, highlighted the major challenge in each and made it east to remember.
He calls it E-E-E-M-I-T. EMIT less and Change the world. Check out the video.