TomaSoft TomaTray 4.1i (Windows)
Source: Tomasoft Corporation
From the developer: ""TomaSoft TomaTray is a great utility that runs in your system tray and is used for monitoring your Windows PC workstation or server. It monitors your computers four most important system parameters while it is active. It monitors the amount of hard disk space used, the real memory used and, the CPU usage (or utilization), and network traffic. TomaTray uses a great analogy that many people can relate to for displaying these parameters. It displays the information in gauges similar to a car's dashboard. When the needle approaches the red zone of the gauge, there is more cause for concern.""