This is a great idea and I just might work in Portland, though I suspect that people will be uncomfortable sharing the yard with strangers - but you might get some real action on the parking strips. It would probably mean toting water, though. Do you have islands on suburban streets there? I used to live in a community where these became guerrilla gardening sites.

My concern about food gardening in parking strips is that it seems parking strips on old or busy streets are liable to have lead deposits from when leaded gasoline was used or asbestos from brake linings. I've read USDA Cooperative Extension recommendations to locate food gardens 100' back from highways.

Also, they tend to become "open-air markets." As in take what you want but don't bother paying.

I don't mean to be too much of a crazy person, but I've mailed a note to the governor asking him to issue an executive directive to free up any space in front of government buildings. I would think that the state could work in conjunction with OSU to create places within open spaces in office complexes to create small community garden areas. We've made a statewide decision to be ahead of the curve on being a "green" state, this would seem to be the next logical step. I'm way out in Lyons, or I'd love to do this. We don't need the grass they have in front of these buildings as much as we need to food growing space in the urban areas.