Camstudio. The veteran screen recorder is back as a free download. Great for making demos, tutorials and the like. Windows only but definitely worth the download for that rainy day requirement.
CamStudio is able to record all screen and audio activity on your computer and create industry-standard AVI video files and using its built-in SWF Producer can turn those AVIs into lean, mean, bandwidth-friendly Streaming Flash videos (SWFs)…CamStudio can also add high-quality, anti-aliased (no jagged edges) screen captions to your recordings in seconds and with the unique Video Annotation feature you can even personalise your videos by including a webcam movie of yourself “picture-in-picture” over your desktop.