--
Portability - if you do lock into a database do you need
to maybe switch DB platforms at a later time? If so,
and you still want a database (I know, more complexity,
but may be worth it in the long run. Not as bad as one
may think, believe it or not)
do you know about the Perl DBI? It's a database interface
with DBD's (Database Driver) for just about any database
you may come up against. Also has ODBC drivers, if you
want that functionality.

If you want an almost-database check out Data::Dumper
or Freeze Thaw. Maybe not the best soltuiotn for you
but may be worth a look.

Hope I've helped,
felonious