1001 for Mac OS X - Allows batch uploading and can notify you of new photos uploaded by your friends.
Background Switcher - Will auto-change your desktop background on a Windows machine at intervals of your choosing from a pool of photos you pick.
Desktop Flickr Organizer for Gnome - Desktop organizer for Linux that allows online and offline work on your photos and tagging.
Flickr and Webimager - Lets you capture your entire screen, or just a portion, and auto-upload it to your account.
Flickr Exporter for Aperture - Tag and upload your photos, store ID and URL for your photos in the Aperture program.
Flickr Exporter for iPhoto -Edit photos, add tags, resize before loading and several other useful options.
Flickr Finder - Mac OS X application for browsing your photos.
Flickr Notifier - An RSS reader that displays photos on your desktop from your friends' accounts as they are uploaded.
Flickr Screensaver v3 - Turns your screensaver into a slideshow of your Flickr photos.
FlickrDown - A program that eases saving photos from Flickr to your hard drive.
FlickrFaves - Java based downloader to retrieve high-res images for your use.
FlickrUploadr - A bulk uploader for Linux.
jUploader - Runs on Linux, Mac OS X, and Windows. Gives you batch uploading and tagging.
Nostalgia - Lets you search Flickr, create new photo sets and synchronize your desktop with your account.
OS X uploader - Uploader for Mac OS X 10.3 and above.
PictureSync - Application for Macs that allows you to upload to Flickr and several other services all at once.
Slickr - A combination download and high-res slideshow in one. Windows compatible.
Upload to Flickr via Windows XP Explorer - Allows you to upload directly from Windows Explorer.
Windows uploader - Drag and drop interface to upload pictures from your Windows desktop. Versions available for Windows 98, ME, 2000, and XP.
Better Flickr - Adds a menu of optional extra features to Flickr.
Fireflix - Sidebar extension to upload, manage and search photos on Flickr.
Flickr Sidebar - Sidebar that lets you search and browse photo lists.
FlickrFox - Lets you browse and search Flickr photos in a sidebar.
flickrgethighrez - Allows you to get a Flickr photo in the highest resolution possible.
Fotofox - Lets you pick and tag photos from your computer and upload them to Flickr and several other image hosts.
OakFlickr4PFF - Adds a Flickr uploader to your browser.
PicLens - Turns your screen into a full size image viewer.
Uploadr for Flickr - Lets you load an image directly from a website to your Flickr account.
Fun & Games
Big Huge Labs - Tons of little games to play with Flickr photos like making badges and motivational posters.
Bubblr - Add comicbook-like word balloons to Flickr photos.
Fastr - Presents you with random photos from Flickr; you have to guess the tag they have in common.
Flickr Chia Pet - Grow Chia hair on any photo.
FlickrLogoMakr - Turn any words into a Flickr-type logo with their font.
Flicktionary - Play a compound word game against it until you can guess what it's thinking.
Hamster Sudoku - Uses images of hamsters from Flickr for you to play a picture version of the popular game.
Matchr - A Flickr puzzle game.
Memry - Play the classic game of Concenntration, but with pictures from Flic
Mosaickr - Creates a mosaic of your master photo using your other photos.
Printr Killr - Lets you make a calendar with your photos.
Spell With Flickr - Spell any word you want, this site grabs pictures of letters to spell it out.
Tag Man - Play the classic game of hangman by guessing the letters in a random photo tag.
The Internet Inferno - As you scroll through Dante's levels of Hell, this page finds matching photos to the theme of each layer.
Ajax Photo Blogging in Flickr - Post a story about the photo you are looking at to your blog.
Flickr 5 Stars Ratings - Adds star ratings to your photos.
Flickr Ad Removal - Hides the text ads on the site.
Flickr All Sizes Menu - Adds a menu to select which size to see when hovering on the All Sizes button.
Flickr AllSizes+ - Allows you to access all sizes for a Flickr photo, copy the code and download the image.
Flickr Auto Page - Removes the need to click on the page numbers to go to another page, adds more to the page as you scroll.
Flickr Auto Tag - Lets you save and reuse tags you use frequently.
Flickr BBCode Generator - Automatically gives you the code to post the image on BBCode sites.
Flickr Contacts Organiser - You can tag each contact, giving you more search options.
Flickr EXIF Decorator - Lets you hover over a photo and puts a translucent overlay in the top left corner which shows you information about the camera.
Flickr GeoRadar - Shows you nearby geotagged images on a radar screen.
Flickr Group Display - Easier group management.
Flickr Image Src Exposer - Adds an â€œIMG LINKâ€ tag making it so you can download any photo.
Flickr Keyboard Navigation - Adds keyboard shortcuts to some of the most common navigation moves on Flickr.
Flickr Mail To - Adds a â€œmailtoâ€ button above photos and also adds a â€œsend pageâ€ link on every page.
Flickr More Home - Add more content to your home page.
Flickr Photo Magnifier - Adds a magnifier to the toolbar to see details in photos.
Flickr Photostream Graphr - Lets you graph how many times your stream has been viewed.
Flickr Quick Comment - Allows you to save commonly used feedback comments and choose the one you want leave.
Flickr Q u i c k r v0.3.3 - Add thumbnail/buddys & NavBar. Also removes all Yahoo ads and bloacked images.
Flickr remove spaceball - Removes the download deterrent image that appears over some photos.
Flickr Rich Edit - Gives you more options in the comments box when it comes to the font.
Flickr Search for Creative Commons - Will allow you to search only on Creative Commons licensed pics.
Flickr Show Licenses - Tell at a glance what the copyright status is of a photo.
Flickr Titles + Descriptions Batch Tools - Adds tools for batch editing titles and descriptions.
Flickr/Shutterfly Integrator - Gives you the ability to order prints of Flickr photos via Shutterfly.
FlickrCommentTools - Allows you to edit HTML into your comments and include your own photos.
FlickrMailManager - Add more options to your Flickr mailbox. Features such as mark all as read, delete all, send notification emails.
FlickrPM - Adds icons for mail, profile, favorites, Scout next to user names, allows you to send messages without leaving the page you're on.
FlickRate - Adds a rating panel under a current photo in an effort to give Flickr a better ratings system.
Geotag Flickr with Multimap - Adds a â€œadd geotagsâ€ link to photo pages so you can add geographical data.
Flickr4Writer - Plugin for Windows Live Writer blogging software that allows you to insert Flickr photos into your posts.
FlickUrPic - Module to let you add your Flickr photos, including private ones, to your Joomla powered site.
Flickengr - Adds Flickr pictures to the bottom of your Yahoo Messenger chats.
Flickr Sets - Enables you to display your photo sets on your Textpattern-powered weblog.
Galleryr - Adds a Flickr gallery to your Blojsom powered blog.
Google Maps in Flickr - Adds a Google map to check the geotagging on the photos without leaving the site.
WordPress Plugins and Tools
FAlbum - Allows you to display your Flickr photos and photosets on your site.
Flickr Comment Importer - Imports comments from your Flickr account into your WordPress blog.
Flickr Photo Album - Allows you to add your Flickr photos to your blog as galleries, also gives you access in the admin area to add them easily to posts.
Flickr Tag Cloud Widget - A sidebar widget for WordPress that shows your Flickr tags in a tag cloud.
Flickr Widget - Display up to 10 photos from Flickr with this widget.
FlickrFaves - WordPress plugin that allows you to display your favorites on your site.
Kubrickr - Replace the â€œblue blobâ€ at the top of the basic WordPress theme, Kubrick, with any image of your choosing from Flickr.
SimpleFlickr - Allows you to embed a Flickr-integrated simpleviewer into your WordPress site.
Chasr - A mini-application that lets you display your Flickr photos on your website.
â€˜Color Fields' Color Picker - Choose a color from the color picker, pictures featuring that color pop up. Good if you are trying to design a website with a certain color scheme. And it's oddly addictive to play with!
Flickr Anywhere - Allows you to display all your public photos on sites such as MySpace.
Flickr Color Selectr - Use a color picker and search only images that are Creative Commons Licensed and match the colors you need.
Flickr Module for CMS - Add Flickr pictures to your CMS Made Simple site.
Flickr Slideshow Generator - Allows you to generate the HTML you need to embed a Flickr slideshow in your website.
FlickrLilli - Search only for Creative Commons License tagged photos.
flickrSLiDR - Allows you to embed Flickr slideshows on your website or blog.
Gickr - Creates animated GIFs from your photos to use on your website.
PictoBrowsr - A photo set viewer to put on your website or MySpace.
Travelr - Free photo gallery you put on your site that allows you to display your photos geographically
FD Flickr Uploader - Background uploading, multiple photo drag and drop. Able to title, tag, enter descriptions, edit privacy settings on each photo. For Mac and Windows.
FlickrNotFrisk - Search photos on Flickr by tags and display the results. You can save images by clicking on search results. For Mac and Windows.
Flickr Upload - Drag and drop interface, allows you to tag before upload. For Mac and Windows.
Flickr Widget - Official Flickr upload widget by Yahoo. For Mac and Windows.
Magic Lantern - Desktop background image changing widget. Windows only. (via)