MOTDstat (Message Of The Day - System Status) will dynamically generate the /etc/motd file with current information about system status and usage. Using crontab, the script will periodically display the status of system resources and services. The original message of the day will be stored in the /etc/motd.orig file. Configuring an email address, you'll receive notifications about the following issues with configurable warning and critical limits: high CPU load, exceeding disk space, intensive usage of swap space, a specific process or network service not running, NTP not synchronized, and too many messages in the mail queue.
Python System Monitor (Psymon) is a cross-platform task and performance monitor. It features global process monitoring, system load history (CPU, memory, network, and disks), disk information, network connections, detailed information and CPU, and memory percentage history per process.
Sentinella is a desktop application that monitors your system activity and, when a condition is met, takes the action that you've chosen. While monitoring your CPU, memory, hard drive, and network usage, Sentinella can be programmed to take specific actions when setpoints for utilization or time are met. It can power off, reboot, or hibernate your system, kill an active process, throw an alarm, or execute any command. Sentinella integrates perfectly with the main desktop enviroments (KDE, GNOME, XFCE, and others) and works under many Unix systems.
Osmius is a monitoring tool for everything connected to a network. It features very high performance. It allows you to create and integrate business services, SLAs, and ITIL processes such as availability management and capacity planning. Osmius offers real GIS capabilities, BI, and data mining to keep track of SLA requirements.