My mind drifts back to earlier days....
Around 1970 Renault offered an unusual (okay, *everything* about Renault was unusual, at least in those days) automatic transmission for the R16. It was a solenoid shifted manual transmission with a powdered iron clutch. The clutch was an electromagnet with steel clutch plates inside and the space inbetween was packed with iron filings. When the magnet was energized the clutch engaged. (I don't know what did the shifting.) I hear their unique creation had reliability problems - I wonder why ;-)
The 70s sure were not the good old days of automotive technology!
Mike