Very handy and flexible - rock stable - small memory footprint - NEW: save as PDF! - under steady development - ...FastStone Capture is a powerful, flexible and intuitive screen-capture utility. It allows you to capture anything on the screen including windows, objects, full screen, rectangle regions, freehand-selected regions and scrolling windows/web pages. It has innovative features such as a floating Capture Panel, hotkeys, resizing, cropping, text annotation, printing, e-mailing, screen magnifier and many more.
IMHO, it's almost perfect!
HP: http://www.faststone.org/FSCaptureDetail.htm