For two years in a row now, this is the best Delphi Conference that I ever attended.
Source code is available for download .
Start Internet Service Manager, go to the scripts virtual directory and right-click to get the properties. DCon2000 - was a big success. What interfaces are, why we'd want to use them, defining interfaces, adding them to classes and implementing them. Delphi and JBuilder source code for this day is still available for download, and so is the final JBuilder and Delphi source code.