PolymonRT
I have been working on some perfmon counter knowledge and came across something I would like to share. If you know what kind of things to measure you can visualize this with PolyMonRT or PolyMon. Yes there are some other products available which look better, but this one is free.
It’s highly customizable so you can get out whatever you want.
Source: http://polymonrt.codeplex.com/
Screenshots: http://polymonrt.codeplex.com/wikipage?title=Screenshots&referringTitle=Home