Not to rant or single you out, but I'm not sure that "programmer" is a sufficient descriptor in this thread anymore since everyone seems to have their own little definition, and I'd argue that solving real world problems is only one of many attributes of "real programming".

Is game programming solving a problem? What about music visualizers? They're both fun distractions, but to call them "problems" is stretching the definition. What about malicious programming efforts? What about using programming languages for the challenge of it (brainfuck, whitespace, etc)?

Refusing to use anything but lisp may make you a poor candidate as an employee or teammate or entrepreneur or whatever, but says nothing about your ability to use lisp effectively.