Adobe’s Linguistic Services team recently launched a project code named Squiggly on Adobe Labs. From the project homepage:
Squiggly is a spell checking engine for Adobe® Flash® Player and Adobe AIR®. The Squiggly library allows you to easily add spell checking functionality in any Flex 3 based text control. The distribution package consists of a utility for building your own spelling dictionaries, a sample English dictionary, an ActionScript package that checks individual words for spelling accuracy, and sample code that demonstrates “check as you type” functionality.