I believe that it is spelled out on the Toyota website that they offer a $200 bounty for each returned NiMH battery, and that they do their own recycling.

The issue always reminds me of a post on the Yahoo toyota-prius site, claiming to quote from a newspaper that Prius batteries were hazardously piling up at some landfill. Searching the web, I could find neither the story, nor evidence that the named newspaper actually exists. Was this a "professional troll" sighting? Hmmm.

http://www.epa.gov/greenvehicles/
http://www.environmentaldefense.org/TailpipeTally/

Will allow you to compare emissions among vehicles. Their results do not always agree, though.

I would like to see a definitive accounting of the financial costs associated with CO2 and pollutant emissions. Published studies vary widely, and as you might imagine these are very contentious issues.

DAS