https://www.youtube.com/watch?v=_YLaq9ynDig
Modified holder to make it compatible with
http://www.amazon.com/Expo-Erase-Markers-Black-86001/dp/B0006HXJFK/ref=sr_1_8?ie=UTF8&qid=1401373557&sr=8-8&keywords=expo+markers+dry+erase
Also modified eraser to have a funnel for easier marker replacement and gave it a deeper channel to fit the expo marker in question.
Included in the files is my modified program written in C#.
I used the driver for the DS1307 RTC provided by http://netduinohelpers.codeplex.com/SourceControl/changeset/view/dfb899d1e153#Hardware/DS1307.cs
The board I used was the FEZ Panda II

For the rest of the parts, reference the PlotClock by Joo
http://www.thingiverse.com/thing:248009

When attaching the bigger holder (biggerholder2.stl), make sure that the extended part of the hand is entirely above or entirely below the other arm piece. if not, then it will get in the way or the arms' movement. Or, just use biggerholder.stl which does not have the extension.