jducoeur

Okay, you're still confined to a single user/computer, but the spell checking on a Mac is a system service, using a common dictionary with all (well, most) programs. If I add Pennsic in Mail, then the dictionary in Safari, Pages, Keynote and most third party apps will recognize it as a valid word. (Microsoft being the major exception - Firefox currently doesn't use the system but has doing so as a goal.)