What software program / equipment is used to make Khan Academy videos?

Sal uses a PC with:
  • Camtasia Recorder ($200*)
  • SmoothDraw3(Free)
  • Wacom Bamboo Tablet ($80)
Prior to that, he used: 
  • ScreenVideoRecorder($20)
  • Microsoft Paint (Free)

Mac users: In lieu of SmoothDraw, Autodesk Sketchbook Express works (free with a Wacom) 
*Camtasia also offers a basic version of their software called SnagIt.