The Royal Opera House is to stream the 20 May performance of La traviata live online. This is not the first opera to be streamed from Covent Garden but it is the first to go out as it happens. It will also be shown free on various outdoors screens around the country.
According to the oddly-worded ROH statement, the event "will mark 25 years of support from BP" - does that mean they've paid for it, or not? Whatever, it's unlikely that the ROH will want to cut into their cinema revenues by making a habit of free streaming, so catch it while you can.