I purchased the Heavenly Shining Beacon of Hope at the Stanford Linear Accelerator garage sale. It’s about four and a half feet tall and has a spinning light at the top.
Lawrence Kesteloot built an optically-coupled serial port interface that let us activate the beacon from any computer in the building.
The beacon was originally attached to an SGI Indigo2. Long after this machine became obsolete, Nick Foster rewired the serial port interface so it would work with a Linux box. He also modified the beacon control software so that the light flashes every time someone files a bug report.
Here is the man page for the program that controlled the beacon at PDI.