This is a true glimpse into history. The source code can be seen here: http://www.masswerk.at/spacewar/spacewar.js
"The original PDP-1 emulation in HTML5/JavaScript running Spacewar! by Barry Silverman, Brian Silverman, and Vadim Gerasimov . . ." I showed my husband. He said, "I knew Brian and Barry Silverman." Here's some more deep computer history. The spousal unit made this movie when he was into software visualizations and he was among the earliest developers of computer animation. This video was made by him in 1969 on a TX2.
Spacewar! was one of the first computer games - 1961-1962 (http://spacewar.oversigma.com/readme.html, http://en.wikipedia.org/wiki/Spacewar!) Pong was the first or second arcade game (with all the logic in hardware as far as I understand) - but not invented until 1972. (http://en.wikipedia.org/wiki/Pong#Development_and_history)