Here is a fun geeky clock that would make a great addition to any geeks apartment or office, the Monochron Pong Clock .
The Monochron Pong Clock was designed by Limor Fried, and the clock is based around a custom white on black 128 x 64 pixel LCD display. The clock displays an endless game of Pong and the time is advanced when one of the sides loses a point.
The Monochron Pong Clock comes as a kit and it is completely open source, which means it is easily hackable and programmable. The clock is switchable between a twelve and twenty four hour display and it even comes with a built in snooze alarm.
If you want one, the Monochron Pong Clock is available for $80 from Ladyada.