Do you use Skype, the free Internet service for making phone calls? If you are a Macintosh user with OS X, you can record your Skype conversations using the instructions given at this site:
Webcrumbs: Recording Skype Calls
This may be a nice tool to use in a distance education (or even a F2F teaching situation (as long as the students have a computer in front of them that has a microphone). After the discussion is finished, the file could be posted on a web page for later accessing, or posted in a Course Management System, such as Blackboard.