Would you like to solve some theory problems and see the results built into a practical, real-world system ? The Internet Business Logic system assigns a highly declarative meaning to a collection of rules and facts. When the underlying base is finite, this can be done. However, in practice we require incremental answers over infinite domains, under the control of a user. This raises some good theory questions that sail close to undecideability. To see the system itself and some theory references so far, please visit www.reengineeringllc.com . If you are interested in getting a precise problem statement, please email me. Thanks ! -- Adrian