Came up as a question in my current SR4 game (i didn't like 5th edition much), after a Troll urban samurai with lots of cyberware had his cybereyes hacked, he didn't like the experience much.
I followed the protocol for finding hidden nodes, spoofing commands and etc. (the attacker had some of the same cyberware, so he knew the interface well enough), the experience wizened up the troll to start upping his game and he wants to know what he can do to make his cyberware more difficult to hack.
Some of the other players are newbie runners, some are not, but most of them have either the knowledge (a Technomancer and a Rigger) or have contacts with the knowledge and enough loyalty to share.
So, anticipating that the other non-matrix player (a mage), i want to know what sort of things can be done to attain a higher level of security with your devices beyond the "slave all cyberware to a decent commlink running on hidden mode"...