I was thinking the same thing Charles. $50 for a UBB Addon seems rather steep to me. That's 25% of the base cost of a UBB license. Not to mention requiring each page to be tagged by their script.
Donate to UBBDev today to help aid in Operational, Server and Script Maintenance, and Development costs.
Please also see our parent organization VNC Web Services if you're in the need of a new UBB.threads Install or Upgrade, Site/Server Migrations, or Security and Coding Services.