Normally I don’t spend time suggesting Add-ons/Plugins for Firefox or other stuff like that, but this is GREAT!
|Cooliris PicLens (here the Firefox Add-on Page), available on Windows & Mac; working with [en:Internet Explorer||IE], Firefox and [en:http://en.wikipedia.org/wiki/Safari_(web_browser)||Safari] (too!!!).|
Just install it, then go on any Flickr, Picasa, Facebook, wathever service that expose an [en:RSS] feed of pictures and… click on the PicLens icon (in Firefox will be in the upper right corner after the installation).
Sweetheart, I’m sure you will love it ;)