I watched the New York conference for Social Good on Live stream on August 28 from the comfort of my desk – no charge. The TED conferences are simulcast for a fee that is considerably lower than the in-person fee. Streaming your live conference allows people to attend who wouldn’t normally attend because of travel or registration cost. Your focus is on the live conference and the streaming happens around that.
Teleconferencing and video conferencing are options where the presenters and the participants are at their own desks listening and/or watching through their computers or phones. The conference is designed around the feed, the feed is part of the message, to paraphrase Marshall McLuhan. There are many free and fee based services.
Other options include: