Other interesting ones:
The shuttle from BHX to its railway station used to be a maglev (years before PVG). Now just cable hauled.
The LHR T5 airside shuttle has public access to the tunnel running underneath. Nice if you like to stretch your legs.
Landside at LHR, one of the car parks is linked to the terminal by an innovative PRT "pod" system. If it gets rolled out to transport people around the airport as a whole, it would be revolutionary.