Here's another way to be interactive with flickr - a cool little find-a-word puzzle.
Check out the puzzle on flickr, log in, and use the Add Note tool to circle words as you find them. Because this is flickr, all the words are either horizontal or vertical, but can be either forwards or backwards.
I put a lot of words in to hopefully let a lot of people play - please only circle a couple words, so everyone can have a chance. All of the hidden words are listed below the image in the description.
I thought this could be a fun thing for libraries to do for their patrons. The puzzle is easy to create (I used a spreadsheet [xls] and print preview - not quite as easy as the library crossword, I admit) and can be made on any theme. I also like that more than one person can work on it, so they can be solved as teams.