PC World has an article on the new Eyemodule digital camera for the Handspring Visor and compares it to the new PalmPix camera for Palm organizers.
The Eyemodule will only add 15mm to the length of the Visor and not add any extra width. It will use the Visor's LCD screen as the viewfinder and have no zoom feature. Color images will take up about 180KB per picture on the Visor. It will also label images with the date/time and include software for image-editing.
The Eyemodule will not replace your camera but is very convenient because of its simplicity and size.