Cybercluster is a synchronous multimaster-replication solution for PostgreSQL. Cybercluster keeps all database nodes in sync at any point in time. When a node fails the cluster will automatically detect the problem and sort out the broken node.
uLan is message oriented multi-master communication protocol for microcontrollers. It uses 9-bit character format for addressing and link control and RS-485 physical layer. More RS-485 cards, converters for PC RS-232 ports and embedded MCUs are supported
Simple set of scripts to add semi-multi-master replication functionality to MySQL server. This could be used effectively to create backup server which would aggregate data from more than one master server with low or moderate insert/update traffic.