Geothis is a project mainly written in JavaScript, it's free.
Chrome extension to analyse a web site and turn it into a map
Geo This! is an extension for Google Chrome that turns web sites into Maps by ananalysing the content. If you highlight a piece of text first only that one gets analysed.
You can see it in action at http://icant.co.uk/geothis
Geo This uses YQL, Yahoo Placemaker and the Google Static Maps API.
The icons were created by Mihaiciuc Bogdan and badly resized by me.