So, if you're exactly like me, you'll find this useful. :) Ok, so I'm currently reading tons of short stories online, and they rarely list their wordcount. When I read a story and I like it, I want to know how long it was, in words, usually so that I can be amazed at what the author did in a few words. ;)
This bookmarklet tells you the wordcount of the text you have selected. So it's a quick way to get that info. Before, I would copy the text to a file and then run a command-line wordcount command (the Cygwin version of wc) against it.
UPDATED 12/14/10: I realized after I wrote this that the real story here is not "there exists a bookmarklet for wordcount" but rather, "when you know about the existence of things like bookmarklets, you can search for them, and odds are someone has made something you can use already." Once this idea occurred to me, it was literally one minute before I had this solution in place. Thank you, Google!