A spell checker and teaching aid from
UK company KeySpell Limited for
Microsoft Windows. KeySpell
offers a selection of phonetically similar words, phrases,
confusable terms, and examples in context. Even correctly
spelt homophones can be checked.
KeySpell can be run with
Microsoft Word 97 or stand-alone.
It includes 225,000 words and phrases and can use subsets of
these.
http://keyspell.com.