Image Exclusion Demo
This is a page with a few images on it.
Some of the images are inserted so that jQuery Colorbox works on them, others are excluded.
Image 1 - Colorbox works
Image 2 - Colorbox does not work because CSS class colorbox-off is configured
Image 3 - Colorbox works
Image 4 - Colorbox does not work because thumbnail is not linked to original image
* Image source: Smashing Magazine