Originally mentioned in <post#=432654>post 432654</post#> in the Lounge Matters forum but cross-referenced here for those who do not frequent that forum.

SpellBound is a spell checker available for Firefox 1.0 and the Mozilla suite. It can be used to correct spellings when you create posts in the Lounge. It is multi-lingual with 50 dictionaries available including English-UK and English-US versions .