Shutter
I already have a good tool for screen shots etc, but found this nice one for Linux it's open source and GPL v3. lots of features too, easy to use and definitely worth a look.
http://shutter-project.org/about/?utm_source=Tiger+Computing&utm_campaign=15a02ea613-TTT_10_SNAP&utm_medium=email&utm_term=0_39417e1d4a-15a02ea613-93251965