I've been working on the Student Line Grapher a lot lately and was doing some research to make sure that no one else had already created the same thing and I found this interesting program C.a.R - Compass and Rule. I believe that the audience is slightly different and the learning curve for C.a.R is harder than the Student Line Grapher but C.a.R also has a lot more features.
While I was browsing the moodle.org website today I found an interesting program AutoScreenRecorder and there is even a free version available. I tried it out and it seemed to work pretty nicely. I appears to be similiar to Camtasia. I'll post some examples from it later.