OS X's Finder is based on PDF, so that's not a bad choice. However, there are quite a few modules for RTF available in CPAN. I've never used them in OS X (mostly because I've never needed to), but that would seem to be worth investigating.
Hope this helps.
--
tbone1, YAPS (Yet Another Perl Schlub)
And remember, if he succeeds, so what.
- Chick McGee