The mysqlnd replication and load balancing plugin for mysqlnd makes using MySQL Replication from PHP much easier. The plugin takes care of Read/Write splitting, Load Balancing, Failover and Connection Pooling. Lazy Connections, a feature not only useful with replication, help reducing the MySQL server load. Like any other mysqlnd plugin, the plugin operates mostly transparent from an applications point of view and can be used in a drop-in style.
Clipping is a handy way to collect important slides you want to go back to later.