Here is a great little free screen capture tool called MWSnap. It has very similar capabilities to SnagIT. Try it out.
Selected features (from Mirek's site)
- 5 snapping modes.
- Support for BMP, JPG, TIFF, PNG and GIF formats, with selected color depth and quality settings.
- System-wide hotkeys.
- Clipboard copy/paste.
- Auto-saving, auto-printing.
- Auto-start with Windows.
- Minimizing to system tray.
- An auto-extending list of fixed sizes, perfect for snapping images for icons and glyphs.
- A zoom tool for magnifying selected parts of the screen.
- A ruler tool for measuring screen objects lengths.
- A color picker showing screen colors with separated RGB parts.
- Fast picture viewer.
- Adding frames and mouse pointer images.
- Multilevel configurable undo and redo.
- Multilingual versions.
- Configurable user interface.
- And more...