Spell The Word is a simple program to improve your spelling. Using Mac OS X's built-in Text-to-Speech voices, the program speaks words for you to spell with your keyboard.
Select from the included word lists, ranging from easy to difficult (including a list of commonly misspelled words), or create your own custom word lists.
Please be aware that Mac OS X's Text-to-Speech voices are good, but not perfect. Also, be aware that it's not possible to distinguish between homophones. Lastly, be sure to have your sound on and volume set to an appropriate level.