atMonitor is the most advanced Mac OS X system monitor and process explorer utility. Data is collected and displayed in the "Activity Viewer", with a choice of either using a beautifully designed floating window that blends right into the desktop without being distracting, or installed in the menu bar leaving your desktop untouched. Some of the unique features include GPU and FPS monitoring as well as ability to explore details of running processes. atMonitor can also be set to log collected information and save it to XML file for further investigation. Triggers can be setup to execute scripts when given resource reaches its target value.

Requirements:
OS X 10.6+
A modern video card is required for monitoring GPU activity
Intel

Limitations:
Project has been abandoned.