Ok, this time it is in the Cells FTP directory: ftp://common-lisp.net/pub/project/cells/uc-ring-net.pdf ftp://common-lisp.net/pub/project/cells/uc-ring-net.sig (signature if desired) That is a very rough draft of a great little use case with a surprise ending I (still) won't give away. I am going to spend a little time now cleaning up the demo code of the solution. In the meantime feel free to request clarifications. Don't worry about proofreading stuff -- I did not even run spellcheck on it yet. After this I will produce text-based tutorials of all Cell functionality (probably in the form of readable source ala "literate programming") and a corresponding reference section (PDF again). kt -- http://tilton-technology.com Why Lisp? http://alu.cliki.net/RtL%20Highlight%20Film Your Project Here! http://alu.cliki.net/Industry%20Application