Peek-a-Boo is the most intuitive way to explore what’s happening in the universe of processes on your Mac. It is a Mac OS X utility to monitor and manipulate all running processes. You can watch how much CPU time each process uses, adjust processes’ priorities, and monitor process information; the innovative process throb window shows in an instant the activity of all the processes on your system.

There are many ways to peek under the hood of Mac OS X with Peek-a-Boo; you can choose between watching overall system behavior in a variety of windows, or zoom in to scrutinize individual process behavior.

Requirements:
OS X 10.6+
64-bit Intel