mySociety yesterday launched a pair of Back o’ The Envelope projects based on Google Maps.
Placeopedia.com — Connect Wikipedia articles with the places they represent
YourHistoryHere.com — Share local and geographic history and trivia.
There are a few things to say about both projects:
1 – As is normal with mySociety projects the code for these projects (excepting Google maps) is open source. We hope that by providing a ready-made annotation system, people will find it easier to make their own publicly-authored layers of information.
2 – Both sites syndicate their data under open source licenses, and in a location-queryable fashion. This is really important, as it allows for all types of nice local history to be syndicated to tourism sites, local community discussion boards, blogs and so on.