Any stock means of inserting a period by pressing the spacebar twice? I've grown to really appreciate the ability to press space twice on my iOS devices and have a period manually inserted without having to switch keyboards.

Though I realize the need isn't quite there on actual keyboards since the key is accessible at all times, I'm curious: Is there any way to get the same behavior using baked-in functionality on Mac OS X?

This is assuming the most recent version of Mountain Lion is installed.
Try this:


Go to System Preferences / Language &amp; Text / Text
Add a new rule where "  " (double space) is replaced with ". " (period space).
Make sure you've got Symbol and Text Substitution enabled, and this new rule checked, too. 


It appears not to work everywhere, though.