The Metaphor and Reality of Silos

Every time someone starts talking about legacy enterprise applications, the term 'silos' jumps into the conversation. Silos are bad. We need to break away from all these old vertical silos to something horizontal, and dynamic, and cool. It's worth remembering a few things about silos:
1) They are designed to hold grain in and keep the rain outside
2) They also keep rats away from the grain
I believe that a new generation of dynamic software will improve the way enterprises operate immeasurably, within the next decade. And I think that whatever solution emerges will make considerable use of silos.