Spell It is an easy to use Mac OS X utility with a minimalistic user interface offering a spelling service.
Selected text is transformed to a list of spelling codes. This list is presented in a small panel and the user may either step through the list and read it or use the speech features of Mac OSX to have the codes read.
A choice of international spelling alphabets is available.
NOTE: Spell It can only be purchased via the Mac App Store (the buy link redirects you to its App Store page). To purchase/download applications via the App Store an Apple account is required.