Master/node to gather and graph "everything" on your systems using Tobi Oetiker's rrdtool. It can optionally warn your surveillance software. This software package was originally called LRRD. The project. Please see http://munin-monitoring.org/
mrsync a tool to transfer files from a master to many remote machines in LAN using Unix socket's multicast. It dynamically adjusts its speed of transfering to ease on the network and to leave no one behind. 4 hours for 140GB to 100 targets in 1Gbit LAN