The other day I was thinking about a campaign-type-of-idea to use snow or ice as a canvas for messages or advertising. Just, you know, storming the brain. 
Yesterday London experienced quite a snow extravaganza and sure thing. The guys from Curb agency swiftly ploughed their way through the white stuff to plant a bunch of Extreme sports channel logos around the city. Nice write-up in Creative Review.
A clever bit of green guerilla marketing.
Then again, my idea was better. Only because it had a digital aspect to it.
Bit less green, but quite a bit more now.
Missed opportunity?