iTunes U opens its doors to the public.

WHERE CAN YOU GO TO SIT IN on a conversation with the Dalai Lama, get a guided tour of the work of photojournalist David Seymour, hear Freeman Dyson discuss Darwin, attend a lecture on modern theoretical physics, and see a panel discussion on podcasting in classrooms?

It's all on the updated iTunes U, a distribution system for colleges and universities within Apple's iTunes Music Store. And it's all free. Apple launched iTunes U a couple years ago as a service within education but has now made the content available to anyone, anywhere.

So far Arizona State University; Bowdoin College (Maine); Concordia Seminary (Mo.); Duke; Michigan Tech; MIT; New Jersey Institute of Technology; Otis College of Art and Design (Calif.); Penn State; Queen's University in Ontario; Seattle Pacific University; Stanford; Texas A&M; UC, Berkeley; University of Maryland, Baltimore County; and University of South Florida have joined the iTunes U ranks. Others are expected to follow.

"We've taken something that was already of great value on college campuses and made it available to the world," says Chris Bell, director of worldwide marketing for iTunes. "This is a great step in the evolution of online learning. It reaches the iTunes audience with some incredibly compelling materials for education, life-long learners, and even [K-12] teachers."

For example, the Distinguished Speaker series produced by Duke's Fuqua School of Business features conversations with leaders of the corporate world. "It's all HD [high definition] video," notes Bell. "It's some of the highest quality stuff you'll see on iTunes in general."

And MIT'S OpenCourseWare project, once all text-driven, now includes video and audio clips to supplement its course content library. "It's the evolution of what they created on their own," Bell says. "What we bring to the party is the iTunes experience and ease of use."