I'm building a simple utility that monitors CPU/GPU heat on Windows Systems. Given that there are heat issues running Vista Glass Aero on Toshiba Tecra models (I'm using an M5) I wanted a simple System Tray utility that would monitor it and show status and temperature. Eventually I'll add some alerting, but just needed something quick.
One feature that I added is showing the historical temperature in a graph. I was writing something to convert the array of decimals into a line graph until I found NPlot.
NPlot is a small (160K) assembly that provides very nice Charting Capabilities. It supports .NET 2.0, 1.1 and even mono (in fact it's built on Mono first).
http://netcontrols.org/nplot/wiki/
http://sourceforge.net/projects/nplot/
The heat issues that have been noted are impacting older systems to the point that it's burning out the GPU and ultimately requires a replacement motherboard in Tecra systems (M3, M4, M5, M7 models all seem impacted).