For those who add audio and/or video to your course material, you should be aware that Acacia Technologies is an intellectual property holding company that claims to own the exclusive right to transmit audio and/or video content to students via the internet. According to Acacia:
"Colleges, universities and schools are making their curriculum available via the Internet on a frequent basis. In many cases, audio/video content is incorporated into the course materials to simulate the classroom environment. Acacias DMT technology covers the transmission and receipt of this digital audio/video content.
Course materials with audio/video content are digitized, compressed and stored for transmission. Upon request from the end-user student, the materials are transmitted via the Internet and are received to be viewed in a downloadable or streaming format on the students computer. This process is covered by Acacias DMT technology. For more information on how the language of our DMT patents applies to these activities, please click here (provided in .pdf format)."
Acacia has already entered into licenses with quite a number of educational institutions and is not reluctant to litigate against those who refuse to buy a license. Their patent portfolio impressed Disney, Playboy, Bloomberg, 24/7, Oral Roberts, and others to enter into licenses as well.
Although I've read a handful of discussions on these boards relating to e-learning patents, I've yet to read anyone's thoughts about the Acacia patents and have only done enough light research to be aware there may be an issue here for the unwary.