Graph the cpu usage of certain processes

Hello again.

Has anyone created a graph that can show the cpu load of different processes on the same server?

For example, we have an OS X server running apache, MySQL, and a couple of other commands.

I'd like a graph that would show: the CPU usage of httpd as a blue line, MySQL as a red line and a couple of other processes each with their own color.

Since there are multiple httpd processes, could they be grouped and have their load added together? I don't need to know how many processes are running, as this is already in procs.

-Eric