I have used the demo to build several products.

1. Serial port interface to a simple token ring network of DS80C320s. Each network node had one or more of the following: IRDA interface or a Scratch build IR interface, serial port to a NT4.0 workstation, silinoid or relay latch drivers, AC triacs, interface to PTAC AC units, credit card readers, simple LCDs. We compiled each unit with just 2 or 3 interfaces and they worked fine. The serial token ring ran on plastic fiber with HP transmiters and recevers. Some runs were over 50 meters. 2k can go a long way on an 8051.

Good luck

Bobby