Spong is a simple system-monitoring package. It features client-based monitoring (CPU, disk, processes, logs, etc.), monitoring of network services, grouping of hosts (routers, servers, workstations, and PCs), host-specific contact and downtime information, configuration on a client-by-client basis, results displayed via the Web, history of problems, messaging (via email or pager) when problems occur, and verbose information to help diagnosis problems. It communicates via simple TCP-based messages, and is written in Perl.
