Rockstar developer

I have thought about this topic for a long time. I remember seeing at one place that an exceptional developer can do work usually done by 10 developers. Or in other words, he/she is a rockstar developer.

Besides productivity, I think rockstar developer has the following traits:

1) Willing to share the knowledge with fellow developers, keep in mind we all learn from each other, rockstar can learn from (dare I say) ordinary developer too;

2) Attention to the details and code quality, and other good development practice such as TDD (test driven development), again sharing knowledge is applicable here;