A good screen capture tool is an important part of any developers toolbox. I love SnagIt - but I have only one license for my home computer. For my other computers I needed to find something free. For the last month I have been using MWSnap. MWSnap is a great tool - but I missed the fact that it does not have built in annotation tools.
I had used FastOne Capture a long time ago - and it was pretty close to SnagIt. Only thing is that the new versions that are available are all shareware versions that time out after 30 days. When I found FastStone Capture 5.3, I almost feel out of my chair! FSC 5.3 is completely free for private and non-commercial use and it never times out. And you can download it from the following site A+ Freeware (FastOne Capture 5.3).
The only thing that I miss in this version of FastOne is that it doesnt automatically post a captured image to the clip-board. (MWSnap and SnagIt both do this).
Here are some more recommendations for free screen capture tools: http://www.techsupportalert.com/best-free-screen-capture-utility.htm