Hi, Graeme!
I think beatr911 proposed the fuel economy run, so he'd be the one to talk to. It has a couple posts in the 'Real Life Get Togethers' forum... you might want to get this thread moved there. I work in Lacey at Woodland Square Loop, but haven't actually been to one of the fairs yet.
It sounds fun though.
The idea was a 'Tour de Sol' type of run, but 'Craig Vetter' ran contests back in the 80's. Also, 'Wayne Gerdes' gets a lot of press for his hypermiling. Google those and you'll get lots of hits. There are other active mileage forums at cleanmpg.com, greenhybid.com and tdiclub.com, but there are more I'm sure.
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