Only by upgrading to Outlook 2003. Hit F1 while in Outlook and search
on "archive" to figure out how to use Outlook's auto-archive feature to
reduce the size of your message store and move old items into an archive
file. At the end of the year, rename the archive file to, say,
archive-<year>.pst, and start saving to a new archive. You can have
multiple .pst files open concurrently within Outlook so you can still
see and search for your old items.