No Snacks, no sweets, no seconds. Except on Days that start with S. Too simple for you? Simple is why it works. Look here for questions, introductions, support, success stories.
I just came accross this article, it's good to finally see mainstream diet advice which suggests avoiding snacks - it looks like they've copied your idea to some extent Reinhard, (though so far I've not seen anything about S days, I think sticking to the 3 meals and no snacks rule 24/7 would be a bit harsh!).
p.s. one thing that bugs me about mainstream diet advice and plans is that they always seem to include some elaborate cooked dish as a lunch suggestion - something not easy to acheive in a shared office kitchen with just a microwave and toaster!