Zebra Mussel filter millions of gallons of water; it's how they feed. The result, the once soup-like Great Lakes are now crystal clear. That doesn't mean the water is unpolluted, far from it. Their output is crystal clear, which for divers is a definite plus. So you see, from a certain perspective, what started as a natural disaster has a definite upside. Now, I know some might argue that learning to love environmental disasters requires a very self-centered attitude. What I celebrate, others revile. I look forward to figuring out what new and clever angle I can come up with the next time we lay waste to some pristine wilderness area.