On July, 2009 I modified the Plugin Quick Flickr Widget. My modifications add the feature to get random photos via TAGS. Creating a better random system. I send a couple of e-mails to ask him to add my feature to the official release, and the answer was that he will take a look.
Now, 2 years later, I was taking a look on the plugin again and I noticed that this plugin never received new releases and updates to the newer WordPress versions.
So I used the Quick Flickr Widget as a base to a new Plugin called Fast Flickr Widget that uses the new WordPress Widget API and adds the random tags feature.
Hope you enjoy,