I'd like to do this without giving feedback to the user as well, because a program I'm making will use it many times.
What didn't work:
scrot
(No mouse pointer)import -window root
(No mouse pointer)xwd -root
(No mouse pointer)fbgrab
(I'm not using a framebuffer, apparently)gnome-screenshot -p
(Big, ugly flash + sound)shutter
(It took a second and a half!)
It would also be great if it would be fast (scrot takes ~ .1 sec to run).
It's fine if the mouse cursor is added later through additional processing.