CamStudio: software wants to be free!
I came across this post from BRAIN_blog (Mohawk College) that reviews a few "dream" research tools. There is a link there that led me to a featured product at the University of Calgary that can make life a lot easier for screencasters.
The product is called CamStudio and it appears to do pretty much what Camtasia does for screen capturing with audio, producing an avi file. The advantage is that it is freeware.
I did a quick test and it seems to work nicely to capture either the whole screen or a section. The one thing it does not have is an avi editor.
I would be interested to hear from anyone who has used this tool.