A restored PDP-1 playing music and running Spacewar!, the first computer game.  It's running at the Computer History Museum in Mountain View, CA, and they do demos at 2pm and 2:45pm the 1st and 3rd Saturdays of each month.
<a rel="nofollow" class="external text" href="https://www.youtube.com/user/toastyken">Kenneth Lu</a>
CC BY 3.0
<bdo lang="en" dir="ltr"><a href="//commons.wikimedia.org/wiki/Commons:YouTube_files" title="Commons:YouTube files">YouTube</a>: <a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=7bzWnaH-0sg"><bdi lang="">Restored PDP-1 Demonstration</bdi></a> – View/save archived versions on <a rel="nofollow" class="external text" href="https://web.archive.org/web/*/https://www.youtube.com/watch?v=7bzWnaH-0sg">archive.org</a> and <a rel="nofollow" class="external text" href="https://archive.today/https://www.youtube.com/watch?v=7bzWnaH-0sg">archive.today</a></bdo>