Graphics:
http://www.flickr.com/groups/gimpusers/ -- The flickr GIMP users group
http://gmic.sourceforge.net/gimp.shtml -- Very capable interface to imagemagick and CIMG
http://registry.gimp.org/ -- Many scripts and plugins
http://gimpfx-foundry.sourceforge.net/ -- Big script package
http://auricle.dyndns.org/ALE/ -- Image stacker for denoising
http://www.mm-log.com/blog/2010-04-05/gimp-edge-avoiding-wavelets -- Halo free sharpening
http://www.logarithmic.net/pfh/resynthesizer -- content aware fill from GIMP

Programming:
http://developer.gimp.org/api/2.0/libgimp/index.html -- GIMP Library Reference
http://git.gnome.org/browse/gimp/tree/ -- GIMP source code
http://www.csse.uwa.edu.au/~pk/Research/MatlabFns/index.html -- Peter Kovesi's image processing algorithms
http://www.cplusplus.com/reference/ -- C++ doc
http://doc.trolltech.com/latest/classes.html -- Qt doc
http://www.boost.org/doc/libs/1_48_1/ -- Boost doc
http://www.gnu.org/software/octave/doc/interpreter/ -- Octave doc
https://developer.mozilla.org/en/Canvas_tutorial -- HTML5 canvas
http://opencv.willowgarage.com/wiki/ -- OpenCV doc

Other:
http://public.hronopik.de/vid.stab/features.php?lang=en -- Video Stabilizer
http://www.mensa.de/ -- Mensa Germany


(cc) by sky#walker