Fleace
Fleace, the Flickr-Enabled Automatic Changer for Everyone, is a free wallpaper changer that retrieves pictures from Flickr based on topics of your choice.

Foldr Monitr
Free tool that runs in the background and watches a selected folder (and optionally subfolders) waiting for you to add photos to it. When photos appear in the folder, Foldr Monitr automatically uploads them to your Flickr account for you.

Phlogre
Photo Organizer for local photos and flickr photos. Meant to replace the official Flickr Uploadr.

Flishr
Windows application to Download, Upload and Search photos from one central command console on your PC.

GratePic
Cross platform tool for posting, commenting and rating photos on flickr.

FlickrSync
Photo synchronization application for flickr users. Manage all your photos locally and FlickrSync will keep them updated in flickr.

rTagger
Organize your Flickr photo collection by modifying tags offline.

Flickr Notifier
An RSS notifier that displays images. The pictures pop up on your desktop in real time.

Mosaica
A customizable screensaver with a content generated by users photostreams

Flickr4Writer
A simple plugin for Windows Live Writer which allows users to browse a Flickr users photostream and insert an image from Flickr into a Writer post. Application of this tool in Flickr4Outlook and Flickr4Word

UploadrXL
A program to upload one or more images to Flickr and add them immediately to your Sets of Groups.

FlickrWallpaper
Simple desktop wallpaper changer that downloads photos based on tags from flickr.

Flickr AutoDownloadr
Windows Application to view Flickr photos in a fullscreen slideshow. Useful for displaying a group of photos on a laptop or TV

FlickrFavs
An application for downloading your favorite photos.

Flickr Explorer
Mass photo downloader for Flickr.

Flickr Importr
A tool for Windows that allows you to upload images to Flickr and automatically add them to groups and sets.

GLFlickrShow
Uses OpenGL to produce fullscreen slideshows with transition effects.

FlickrDown
Downloading photos from Flickr to save locally easier.

Grabbr
A small application to smooth the task of uploading screenshots to Flickr.

Flippr!
A simple application that grabs pictures from Flickr and puts them on your desktop.