Tweet Clouds let you know what it is you can't shut up about
That's not exactly what Tweet Clouds does. But the site does analyze all of the messages you send over Twitter to create a tag cloud. So it's almost as good, right? It will show you a list of your most frequently used words. And the more often you use a term, the larger the font will be. If you've set up an automated system to send out a tweet every time you write a new blog post, there's a good chance you already know the words that will pop up most often.
The site is pretty slow, especially if you've sent a lot of tweets in your time. You can suppress @reply messages if you want to filter your tag a bit.