Freeway blogging is... well this:
It's a brilliant idea, started several years ago during the Bush administration by a blogger out west. Post a politically impactful sign above a highway and get tens of thousand of impressions during the morning rush hour before it gets taken down. He's got an amazing collection, and now is running a contest for a good sign/slogan about global warming. The winner gets their slogan plastered along the west coast and a thousand bucks. Check it out.
