For posterity, or current users, just a note to say that thanks to c:amie and his splendid work:
https://www.hpcfactor.com/support/cesd/200060/known_issues_with_the_...
the MA701
(THE go-to card for the Zaurus
) does the job on the Sig3. It'll suck your battery in more ways than are good, but can be successfully disabled via DevPSwitch
(what a great app
). I can't yet tell if its power management is actually working: those menu ticks are sometimes aspirational.
Jake
And to the others who were the foundation of the article! 