Shutter is a feature-rich screenshot program. You can take a screenshot of a specific area, window, your whole screen, or even of a website – apply different effects to it, draw on it to highlight points, and then upload to an image hosting site, all within one window.It's in the Debian repositories , but it is buggy !
The one from their site/PPA works fine. You first need to install xulrunner from experimental and gnome-web-photo from Lucid ( you will get a warning about node gettext domain not understood below schema , but that won't spoil the fun ). Now you can download shutter_0.86.4~ppa4_all.deb from this page .
Update Apr 17 2011 : xulrunner-1.9.2 no longer available from Debian, use this package instead : http://packages.ubuntu.com/lucid/amd64/xulrunner-1.9.2/download