This piece represents a small departure for me in that it also displays the characters A-F that form the hexadecimal number base as used in computer coding.  Sometimes it will spell 4 letter words as it randomly changes.

The visible electronics were found loose in a surplus store in Oakland, CA.  It consists of a big glass neon display, and a second driver board below that uses many old and dated driver chips.  I added a randomizer circuit inside the base to ensure that the numbers are completely unpredictable.