One technology that I believe is increasingly useful in open education is Google hangouts.
Hangouts provide free video conferencing though it only allows 10 video participants, each of whom is required to install the chat plugin from Google; the chat/text hangout allows 100 participants. The video hangout, however, can be streamed to YouTube and chat enabled there too which can therefore enlarge the scope for greater numbers.
It is possible to share documents and screens, so it can be a good environment for working on collaborative projects at a distance as well as hosting discussions, viewing demos etc. Google ran their own education conference season and it provides an interesting example of what might be possible in the future: https://sites.google.com/site/eduonair/home.
It is important for open education because it is free and yet, with minimum technical requirements, can enable anyone to create a learning experience.