Here is a nice little application that I stumbled across when browsing CodePlex today, Taskbar meters. Taskbar Meters adds two(soon to be three) meters into your Windows7 taskbar that keep you informed of your CPU and memory usage. A third meter for hard drive usage may soon be added as well. The main advantage that I see is that you dont need to open windows task manager or any other 3rd part software to see your system usage data. You can easily identify the usage by glancing over the windows taskbar and visually seeing the level of usage of each CPU and memory.
» Read more: Spice up your Windows 7 Taskbar with Taskbar Meters