Submitted by [Scott Gayou] has a Subaru, a car that has an all-in-one entertainment system head unit that is typical of what you’d find across a host of manufacturers. His account of jailbreaking it is a lengthy essay and a fascinating read for anyone. He starts with a serial port, then an SSH prompt for a root password, and a bit of searching to find it was made by Harman and that it runs the closed-source realtime OS QNX. From there he finds an official Subaru update, from which he can slowly peel away the layers and deduce the security mechanism. The write-up lays bare his techniques, for example at one point isolating the ARM assembler for a particular function and transplanting it bodily into his own code for investigation.
A very good account of this obscure jailbreaking adventure.
I was considering installing custom firmware in my Sony XAV-AX100 receiver to get rid of an annoying nag screen on startup, but they released updated official firmware that auto-dismisses the nag. I love hearing about this kind of initiative.
There are so many software driven gadgets out there, where one (at least me as programmer) wishes to get hands on and tweak it here and there.
Or those which are not updated at all. My Opel audio equipment for example.