What does an online conference for 3000 scientists cost? "The conference was free for all participants. The running costs ($150 for a Crowdcast subscription and $60 for Amazon Web Services) were covered by lab start-up costs." @eLife https://doi.org/10.7554/eLife.57892

I further suspect that the drinks were cheaper than $11 hotel beers.

Also, this: "Crowdcast allows anyone to submit a question to ask the speaker at the end, and viewers can vote on those questions. This led to a question and answer session that was considerably more lively and democratic than in a typical legacy conference"

And: "The third innovation is the chat window that appears alongside the talk. We did not anticipate how significant this would be. Students and others were able to ask basic questions about definitions or ask for links to papers while the talk was going on."

The organizers have a broader essay describing their conference agenda and experiences on @medium https://medium.com/@kording/how-to-run-big-neuro-science-conferences-online-neuromatch-io-49c694c7e65d Very impressive international attendance!