Tickr is a Mac OS X application that provides a moving ticker of images from Flickr. These can include a ticker of images from a specific user, from a tag, or from search string. The ticker can be positioned on the left, right or bottom of your monitor. Image size can be adjusted, along with opacity. Images can float above other applications, behind, or as normal application. A very nice integration of Flickr on the Mac.
By way of FlickrNation