http://www.michaelfogleman.com/imeme/

iMeme is a meme generator for Mac OS X.

* Over 50 built-in templates.
* Enter your own header and footer text.
* Adjustable text size and alignment.
* Use your own images.
* Save as PNG or copy to the clipboard.
* Print directly from the app.
* Automatically upload to imgur.
* Automatically post to reddit.
* Works on OS X 10.5 and up.
* Works on Windows XP and up.