I agree and disagree with you, Shadow Stoner Wolf.
The known universe is more immense than most people can wrap their minds around, but I don't think that makes us insignificant. You said, "Every individual component is meaningless without the rest". I don't think we're excluded from that. We're expressions of the universe, just like everything else on this planet. The difference is, most people don't realize it, and so we feel that we've become something seperate from nature. I think it's this feeling of alienation that creates such an incredible hostility and/or indifference in people.
In the grand scheme of things, I don't think we do nothing. We react to the energy around us, just like everything does. I don't see why we need a purpose beyond that, though.