I like that there are a number of YouTube clips where we get to see performers debuting a song for an audience. The songs are familiar to us by this point, and hearing the crowd not cheering at the opening notes is refreshing. Here are three of these debuts, in reverse alphabetical order for no particular reason.
The Police introduced "Message in a Bottle," not only to a live audience, but on television. This was back when Sting had stones.
Here's Bob Dylan playing "Blowin' in the Wind" to a television audience. The host doesn't seem all that impressed...
Best of all, here's Johnny Cash doing "A Boy Named Sue" at San Quentin. Yes, this is the original performance to the very definition of a captive audience that still gets played on the radio today. Seeing the prisoners' delight adds another dimension to the song, as does watching Johnny reading the lyrics off a music stand.