Technically, there should be no reason why Windows CE 4.X.net could not be easily ported (or even run straightforwardly) on the 770. Its main architecture is not that different from e.g. the Siemens SimPad SL4, which can run WinCE and embedded Linux.

As an owner of both a Wince-d SL4 and a 770, my reaction to the original question is: Why? For the love of Bog, why!?

Trust me...