Cooliris has created a really interesting image viewer add-on for your browser.  PicLens is a full-screen viewer for multiple images, whether in slide-show format or in a “wall” of images that can be clicked, dragged, zoomed, etc.:

It is available for various browsers, including IE, Firefox and Safari.  I have tried the IE and Firefox ones and I can say that the IE one is a disappointment when compared to the Firefox add-on.  IE only offers a 2D view and a slideshow, while the Firefox version really shows off the wall function (Flickr credit to t-dot-s-dot):

Download and install this add-on and go visit your favourite Flickr page, a Google Image search result, and more.  They even have a WordPress plugin so that it can be incorporated into a personal site as well.