Some of you may already know and be using Flickrshop from Pixelnovel, but for those of you that haven't heard of it, it is a wonderful little plugin for Photoshop CS2 and above; Best of all It's free if you only want to upload a maximum of 3 images per day to flickr. If you want unlimited uploads then you can buy the plugin for just $19.99.
Just download the exe file and install, then when you have finsihed editing your masterpiece in Photoshop, just go to file>automate>flickr shop. The first time you upload you will be asked to authorise the the app with flickr, once done, you will be able to upload straight to your sets, add tags and descriptions all without leaving Photoshop. Brilliant!
Flickrshop is available for Mac and PC.