When we shipped Windows Mobile 6, it came with a relatively unknown and hardly used API called WISP Lite. WISP stands for Windows Ink Services Platform. It is the same API that is used for the Tablet PC. WISP Lite is a subset of WISP and has been ported down for Windows Mobile.
Mark Arteaga from the OpenNETCF team has written a really good article about using WISP Lite on the mobile device and sharing the "ink" that is captured in the Ink Serialized Format (ISF), with the Desktop WISP platform.
Great work Mark.