FoxPro...
I ran SCO FoxPlus for Xenix for years. It was excellent and ran flawlessly on FreeBSD. It did however fall into the hands of Microsoft and later appeared as FoPro Unix (!?!?), which was excellent. In fact I think I may still have the documentation set somewhere. However after Microsoft discontinued it I moved to Harbour. We still use it today. I highly recommend it to anyone who needs to get a text mode multi-user system up-and-running in short order.