This is a simple little browser extension (Safari only at the moment) to enable auto-smart-quotes and other small typographic niceties while typing in text boxes of any sort.
Note this is pretty early stage and experimental; it needs some work to really be worth distributing widely. See the issue list. Feel free to file new issues or contribute!
This code copyright 2014 Rob Brackett and is licensed under the BSD 3-clause license, the full text of which can be found in the LICENSE file.