This also works on the eInk screen:

The pen that comes with the Motion Computing LE1700 tablet PC works.

Motion Computing Item Description:
504.500.01
Additional Digitizer Pen - L-Series.
As of 10 April 2010 $34.99 from the Motion Computing store.

https://store.motioncomputing.com/TA...elID=3&TabID=1
http://www.motioncomputing.com/choose/spec_pen_L.htm

This pen is larger and heavier than the generic Penabled pens from Wacom in the original post. The LE1700 pen is sized like a nice, executive pen with rubber grip in the right place. In the size vs heft category the LE1700 actually feels more substantial and rugged than the Wacom pens. The LE1700 pen also has a lanyard hole in the end, so it can be tied to something to prevent it being lost. Also, considering the Amazon price for a much more cheap feeling pen (with eraser), this is only $1 more from Motion Computing.