Excalibur is the open source Macintosh spell-checker For Mac Classic or Mac OS X Systems
Excalibur is a TeX/LaTeX aware spelling checker. It will also spell check plain text documents. Excalibur was originally designed to work as a spelling checker for LaTeX documents, but it can be used to spell-check any text document, including text in the clipboard. Dictionaries can be customized for personal needs, and foreign dictionaries are available.
# Operating Systems:
Mac OS Classic
6.0.5 on up ...
# Additional Requirements:
Mac OS 8.6 or 9.x with CarbonLib, or OS X 10.x
# Limitations:
No limitations
# Date Added:
October 28, 2007
The latest version of Excalibur is version 4.0.7. It requires Mac OS X 10.2 or later and it's Universal Binary.
Version 4.0. This version requires Mac OS 8.6 or later and supports Mac OS X.
Version 3.0.2. This version requires a PowerPC running System 7.1 or higher with the Appearance Manager installed or System 8.0 or higher.
Version 2.6. This version will run on any old Macintosh (PowerPC or 68K) running System 6.0.5 or higher. It will even run on a Mac Plus.
http://excalibur.sourceforge.net/downloads.html