Tina pointed to DestroyFlickr, an excellent AIR application for viewing Flickr photos.
DestroyFlickr explores alternative methods for viewing and sharing Flickr content. Its user interface provides an environment that benefits photos rather than hindering them. With the ability to look at a photo on a dark, neutral background, you can view it without the interference of a brighter surrounding. By using workspaces and canvases, DestroyFlickr is able to retain a constant history of where you have navigated, offering the ability to revisit an area without the need to reload the entire page. DestroyFlickr takes advantage of features provided by the Adobe AIR SDK that are unavailable to web-based RIAs. With the support of both drag and drop uploading and downloading, posting and saving photos is done in one easy motion. Now you can download the highest resolution version of a photo without having to see it first—just drag a thumbnail to the download menu and the download begins.
Disclaimer: DestroyFlickr does not intend to replicate or attempt to replace the essential user experience of Flickr.com.