Does anybody have a green roof? 

How green are we talking? Down at the corner there's a house with green-tinted shingles, but no pistachio tin roofs within a close radius (maybe out in the rural areas...)

Green as in there is stuff growing on it, maybe different grasses and low lying plants.  More popular in Europe than here, I get the impression.  I saw a picture of one that was pretty steep and it had a goat grazing on it.  I thought it was neat. 

Oh, sounds cool. I do know some people who live in a house built in the side of a hill. The roof is flat grass (and has a sign forbidding 18-wheeler parking). Europe is great for that kind of stuff.