There are many poor scripters out there, luckily. I have IE Booster browser extensions installed (very useful btw) . If you can get the contextmenu of the page there you choose "show images"and a new window opens with a list of pictures without rightclickblocking. Did so far work everytime. Apart fom that as far as I know anything that's on your screen is already saved in your temporary Internetfiles and you can pick it up from there.
Catch, if you can teach webmasters to safe things frome saving, pleaaaaze don't.