Inexpensive Fax solution

I am running a NetWare 4.11 server on a small network of about 22 Windows 98 computers. We receive and send a lot of faxes on a daily basis. We are not using GroupWise as our email system! We’ve opted to use Pegasus Mail instead as it has all the functionality required by the business and it’s free!
Are there any inexpensive (free) solutions out there? Please let me know!