This week, the OCW Consortium is holding its annual meeting, celebrating 10 years of OpenCourseWare. The movement to make university-level content freely and openly available online began a decade ago, when the faculty at MIT agreed to put the materials from all 2,000 of the university's courses on the Web.

With that gesture, MIT OpenCourseWare helped launch an important educational movement, one that MIT President Susan Hockfield described in her opening remarks at yesterday's meeting as both the child of technology and of a far more ancient academic tradition: "the tradition of the global intellectual commons."

We have looked here before at how OCW has shaped education in the last ten years, but in many ways much of the content that has been posted online remains very much "Web 1.0." That is, while universities have posted their syllabi, handouts, and quizzes online, there has not been -- until recently -- much "Web 2.0" OCW resources -- little opportunity for interaction and engagement with the material.

But as open educational resources and OCW increase in popularity and usage, there are a number of new resources out there that do offer just that. You probably already know about: Khan Academy and Wikipedia, for example. But in the spirit of 10 years of OCW, here's a list of 10 cool OER and OCW resources that you might not know about, but should know:

P2PU: The Peer 2 Peer University is a grassroots open education project in which anyone can participate. Volunteers facilitate the courses, but the learners are in charge. P2PU leverages both open content and the open social web, with a model for lifelong learning. OpenStudy: OpenStudy is a social learning network where independent learners and traditional students can come together in a massively-multiplayer study group. Through OpenStudy, learners can find other working in similar content areas in order to support each other and answer each others’ questions. OpenStudy supports a number of study groups, including those focused on several MIT OCW courses. NITXY: NIXTY is building a learning management platform that supports open education resources. Rather than an LMS that closes off both academic resources and academic progress, NIXTY is designed to support open courses so that schools, teachers, and students' work is not necessarily closed off from the rest of the Web. OER Glue: Still under development, OER Glue will be a site to watch. The Utah-based startup is building a browser-based tool that will allow students and teachers to "glue" together OER resources online. Rather than having to copy-and-paste resources into a new setting, OER Glue will reuse and integrate resources. iUniv: iUniv is a Japanese startup that is building web and mobile apps to support and make social video and audio OCW content. Resources can be shared to Twitter, Facebook, and Evernote so that students can actively engage in discussions around OCW content. OCWSearch: OCW Search is a search engine dedicated, as the name suggests, to helping learners find OCW content. The project is, unfortunately, no longer under development, but it does index ten universities' OCW content, including MIT, Notre Dame, and The Open University UK. Smarthistory: Smarthistory is a free and open multimedia website that demonstrates how very heavy, pricey, and obsolete the traditional art history textbook is. CK-12: The CK-12 Foundation's Flexbook platform provides free, collaboratively-built and openly-licensed digital textbooks for K-12. Much of the content is standards based. Flat World Knowledge: This is a college textbook publisher whose books are published under an open license. This allows professors to customize the books they order – edit, add to, mix-up – or use as-is. Students can access the books online for free or can pay for print-on-demand and audiobook versions. Connextions: Connextions is a repository of educational content, containing over 17,000 openly licensed learning modules.

If you know of any other great OER and OCW resources, please let us know in the comments!