I’m using a nice screen capture tool called Bug Shooting. The latest version is available for a modest fee but the previous version is still available from the author as freeware. It’s a bit hidden mind.
It offers nice cropping, highlighting and annotation features and it integrates nicely with various bug tracking apps such as Fogbugz, JIRA and SpiraTest. It also saves your grabs in a sensible format (JPG, BMP or PNG) or copies them to clipboard.
I found this to be a neat replacement for the Fogbugz Screenshot Tool. This is a beautifully simple tool but sadly is available only with Fogbugz.