Blinkenlights (name inspired by the jargon file entry noded above) also is the name of a light installment made by german Chaos Computer Club (CCC) at the Haus des Lehrers (House of the teacher) in Berlin, Alexanderplatz.

The basic idea was creating world's biggest Pong game to celebrate the 20th anniversity of the CCC. The house was empty due to renovation works, so a 8x18 pixels monochrome dot matrix was created by using 144 floodlights to illuminate the windows in the upper eight stories.
You can call the game using your cellphone and play Pong against the house or against a human opponent via dial tones.

While no one plays, blinkenlights displays random animations including ALL YOUR BASE ARE BELONG TO US, the CCC logo and many more.
As a third feature, you can produce your own animations using free software from, thus creating loveletters you can display on the house by calling a phone number and enter an activation code, so your loved one will see it while you are wandering through nightly Berlin.

Blinkenlights will stay at least till the end of February 2002.

Update March 2002: It's gone now, sadly.

Some technical facts about blinkenlights:

Die Datenschleuder Issue #76, Fall 2001 (CCC member magazine)