Collabrowsers is a flash application using Flash Communication Server to allow for a realtime chat and realtime data transfer of the current browsed url. It is using ShiftSpace to be inserted as a transparent layer above any website. Data passed through ShiftSpace to the Flash movie and through it to the FlashCom allows the users to know which site their peers are browsing at any given moment and join them at that site.
This is the sourcecode for Collabrowsers:
demo page – It will not work without ShiftSpace which is still unavailabe for public Beta (or Alpha)