I had an idea that i'm sure people have thought of and if they have, i want to know about it. Anyway wouldn't it be cool to have a program which uses GPS to show you user-contributed information about the places near you. For instance you drive up to a resteraunt and see a review by someone cautioning you against a particular dish. Maybie a note saying watch the hell out, cops like to hide over the hill ahead. Even some peice of history about a monument in a town square. You could make a note over your house welcoming people to use your wifi. A link to a relevant website. Any interesting tidbits or life lessons about the particular location. What i envision would follow a wiki-like content model where anyone could contribute.
There would be a standardized protocol that could be accessed by different types of clients. There could be a mobile cleint for in car pcs and the like that is mainly geared toward presentation. There could be a non GPS linked version for use on a home pc that is something like an editable google earth.
edit:
seems such a thing does exist
http://wikimapia.org/
Its a start but not as open or full featured as what i imagine. Not quite the attitude either. Most of the comments are "Place X is here and here is a wikipedia clippings on it. I envision more of a hitchhikers guide of sorts. Also lacks an api.
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