Coloriage allows colorizing B&W photos and replacing colors in color photos. It's enough to indicate the desired colors by a brush stroke; the program recognizes the object's border itself and tailors the new color to the grayscale tones of image.
FotoTagger is a tool for image annotation. Add notes pointing to specific objects. Display or save tags in a form of balloons. Upload/download images to/from Flickr. Publish images to blog. Create Web slide shows. Search, hide notes. Organize images.