This one is a nice tool for bloggers and designers: all the images I use in my blogs, websites, presentations, etc. tend to come from searching Flickr for photos licensed under Creative Commons. To make my life easier, I created a search plugin for Firefox that will add this search to the little search bar at the top right corner of the browser windows. Since this plugin follows the Open Search specification, it is supposed to work on other browsers as well, such as IE7 (IE6 has no support for Open Search plugins).
To install the plugin, download the .xml file, and copy it to the “searchplugins” directory inside your Firefox profile. In Linux, this is typically located at “/home/<user>/.mozilla-firefox/<profile-name>/searchplugins”. In Windows, I believe it should be in “Documents ad Settings\<user>\Application Data\Firefox\<profile-name>\searchplugins”, or something like that, but I’m sure you can find it. So put the flickr-cc.xml file in there, restart Firefox, and voila, you can now search Flickr for images under the Creative Commons license directly from your browser’s search box!
And before anyone mentions it, I am aware there are better ways to provide installation for this, but they generally involve Javascript, and right now I don’t have much time left to fiddle around with that 
Automatic install
Thanks to this plugin, I found a way to change the HEAD data for a single page in the blog, so now if you visit this post’s permanent URL, you will be able to add the search plugin automatically by opening your search engine list (click on the arrow to the left of the search box), and you should see an entry “Add Flickr Commons Search”. Click on that and the plugin is automatically installed (on Firefox anyway, I have no idea how this works in IE).
Download the plugin here!
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