Is geo-engineering a real solution for climate?

Here's a great article on some outlandish but intriguing geo-engineering ideas that are starting to get more attention.

 The ideas are shrouded in controversy -- "Why are we speculating about whether we can construct concrete trees that may or may not effectively capture carbon from the atmosphere when we've got people's homes which aren't properly insulated? That's absurd," -- but still quite fascinating and fun food for thought leading into the Global Summit in Denmark next month:

 If there were some kind of panic button to stop global warming, what would it look like? How about billions of tiny mirrors, launched into orbit to deflect solar rays away from Earth? Or big, fluffy clouds, artificially whitened so they reflect more sunlight back into space? Or maybe mechanical trees, ugly but effective at sucking carbon dioxide from the air along busy highways.

Read more: http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2009/11/26/MN2H1AKSHS.DTL#ixzz0YIpCiVP2