Is there still enough GroupWise out there to make a calendar migration tool worthwhile?

We've been having such success with how easily the "faster, simpler" method works with Zimbra and Oracle that we're wondering if there's any demand for any other calendar migrations that have been under-served.  The one that comes to our minds is GroupWise.

Anybody want an easy way to migrate their GroupWise calendars to Exchange server-side?

Let us know.