I was wondering if there were any projects out there to replace/mod the Idrive system.
I've been looking into it myself, and it seems like the biggest road block is the fact that the cars use a fibre optic MOST network, and getting access to any MOST adapters without being a major auto mobile company is near impossible.
If you could somehow get access to a MOST to USB or a MOST PCI adapter it would be relatively simple to capture all the packets sent across the network due to it's bus topology, and even start reverse engineering them (as communication on a network like that is unlikely to be encrypted) to allow a Linux or Windows based computer to do everything Idrive does.
So if anyone knows where to get a hold of MOST to PC hardware that would be amazing.
Also - it would be a lot more work... But another alternative is if someone could identify the cheapest and most readily available MOST module used in these cars (as I'd likely end up destroying at least a couple). It would have a lot of the requisite hardware needed to start reverse engineering the MOST network.