Textiled Smarty Pants
SmartyPants is a free web publishing plug-in for Movable Type that easily translates plain ASCII punctuation characters into smart typographic punctuation HTML entities.
It may be noted that SmartyPants can work in conjunction with Brad Choate's MT-Textile plug-in. MT-Textile is a port of Dean Allen's original Textile project to Perl and Movable Type. MT-Textile by itself only translates Textile markup to HTML. However, if SmartyPants is also installed, MT-Textile will call on SmartyPants to educate quotes, dashes, and ellipses, automatically.
Using SmartyPants in conjunction with MT-Textile requires no modifications to your Movable Type templates. I had mine to automatically use Textile 2 for "Default Text Formatting for new entries", it also became automatically available on the desktop blog publishing software, Zempt which I am using. Go to your MT Weblog Config > Preference and select Textile 2 in the "Specifies the default Text Formatting option when creating a new entry".
With the release of MT 3.1, you have another option of text formating, mark down. Mark Down can be used in conjunction with Smarty Pants.