I, too, have been pondering the "cute little friendly horn" in the Cube. With big powerful sound systems in cars, people on their cell phones (regardless of the hands-free laws), and other distractors, sometimes a big powerful horn may be necessary to rekindle the consciousness of the other driver. On the other hand, something extremely unusual like the train, especially in an area such as ours where we have a lot of commuter trains, may really freak the other driver so much, they compound an already risky situation.
So, I got to thinking about how often I really use my horn and except for a very rare occurence as mentioned above, most of the time is to nudge someone gently into action at a green light they have not noticed. So, while I would like a big blaster for that one situation where it may be needed, defensive driving is still a better answer. However, if you can show me where to install something really cool, let me know; how about the Good Humor truck bells at least for those of us with pearl white cubes???