If you're anything like me, you probably go hunting for reference images for mapping/modelling/texturing etc, open scores of images and then find it's a total pain in the arse to manually save each image. However, help is at hand. I found this Bazzacuda firefox extension (click) which does the business for you
All you do is open the images you want to save in tabs, then, once they're loaded, use the extension's functionality to save all images. It can even discern between pages with various image styles (like other images on the page or dynamic web pages like .asp with embedded images).
Anyway it's so immensely useful when resource gathering that I thought I'd post it here.