There are a number of other sites out there that encourage people to share their work and collaborate in developing new content that benefits everyone. Here are a few of our favorites.
Put together by ACRL this site contains peer reviewed instructional material designed by librarians. Content can range from broader information literacy tutorials to a few database tutorials. (ANTS differs from it in that we began our project by focusing on creating current tutorials for e-resources - whose interfaces are constantly evolving - and hence do not incorporate peer-review as many products would have changed interfaces by the time they were peer reviewed.)
EOL is a "Comprehensive, collaborative, ever-growing, and personalized, ... ecosystem of websites that makes all key information about life on Earth accessible to anyone, anywhere in the world. Our goal is to create a constantly evolving encyclopedia that lives on the Internet, with contributions from scientists and amateurs alike. To transform the science of biology, and inspire a new generation of scientists, by aggregating all known data about every living species. And ultimately, to increase our collective understanding of life on Earth, and safeguard the richest possible spectrum of biodiversity."
Although this is not a sharing site for libraries, it is one that demonstrates the potential of technology to allow people across institutions to work together and achieve something great.