Neighbornode is a captive portal on a residential Wi-Fi hotspot, containing a message board.
It is designed to help neighbors who share an internet connection know each other better.
[1] The message board can only be accessed within range of the hotspot.
Individual Neighbornodes can be linked together to create a supernode, vaguely like Fidonet.
It is implemented as an alternative firmware for the Linksys WRT54G router.