Sven Van Caekenberghe is the author of some interesting Common Lisp hacks, including KPAX, a nice (web) application framework, and cl-prevalence, which is the one that drove me to his homepage. And there i found his Lisp Movies.
Bets are seasoned common lispers will be well aware of them (the screencasts are more than a year old), but new CL aficionados or anyone wanting to see the much touted dynamism of Lisp in action will find in this couple of movies a good example of how it feels programming web applications within a really powerful environment. Sven interacts in this two-episode series with LispWorks to create a simple HTTP server (and modify it on the fly) and to write a Reddit clone in 20 minutes and 100 lines. The latter uses KPAX, so, as a bonus, you’ll get a mini-tutorial on the framework.
But of course the nicest bit is seeing how one starts with an empty but running server and modifies or, rather, debugs the program until it behaves properly. All that keeping it alive and using the tools provided by the environment (inspectors, listener, debugger) to bend and evolve the code. Ah, the Joy of REPL once again.