One of my favorite Flickr Mashups is Bubblr. Bubblr searches the Flickr database on one of two levels: Tags and Usernames. You can take the images and arrange them in a comic strip. From that comic strip, you can create whatever dialog you choose with conversation bubbles. (Hence the name: Bubblr) Then the finished product is saved in the archive, where it is public. Bubblr conscientiously reminds us that your boss could technically find this strip and fire you if it is incriminating.
The comic strip can then be shared by a variety of means, including: print, emailing, blogging and del.icio.us.
As for the content of this stip, no it's not my most creative work. But it illustrates the basic features of this mashup.