Ask HN: Looking for a free / cheap hosted HTML5-based Webinar/Training platform

I'm looking to run a few online courses with a live instructor with slides and some video. There are number of solutions that require either the attendees or the trainer to use a desktop app or other download to either deliver the training or attend, or both. I'm trying to find something with no such requirements.

The meetings will have slides, require chat with trainees, and allow for viewing videos and perhaps cameras. The sessions need to be recorded for future viewing by trainees.

I've tried BigBlueButton, but there's no credible hosted solution, and I'd rather not have to go through the expense and trouble of running my own BBB server and managing it. There are very few third-party hosted BBB solutions, but if there was one that offered long-term recording storage as well as just BBB hosting that would be great.

Right now, there are very few web-only / web-based training solutions that don't require downloads and also record the webinar / training for future use.

I'm hoping something is out there that fits the bill!