I tried out this free screen capturing software (with audio) and I can see this is something I may want to use for quick tutorials. Exports video in .mp4, .avi, .flv, formats and assists in uploading to YouTube or to your computer. The pro version gives you the ability to edit, etc. and is only $12 a year. Try this app out!
Snaplr is a simple way to capture and annotate your desktop's activity. Its Free to download. After taking your screenshot, you can highlight a specific screenshot area further with a set of drawing tools. Copy your screenshot to the clipboard and paste it to an email or save it as a png attachment instead. Works great in Gmail and Outlook. I like using this in Windows as Google Chrome doesn't have the best screen capture extensions right now that can annotate as easily as this tool.