The McLaren Senna has an incredible rear wing. Top mounted, just like a GTE race car, but unlike one of those, it's active. Working in concert with dual-flap wings in the front fenders, the rear wing constantly changes its angle of attack over the course of a lap. Under braking it rises to help slow the car down, and at full throttle it stalls to give a DRS effect. Watching it do work its magic is mesmerizing.
Seriously, I can't stop watching the thing. Autocar put up a 360-degree video of a lap of the Silverstone International circuit, and I'm totally fixated on the wing. I've watched this video a number of times, just trying to figure out what the wing does.
It seems to be always moving, rising ever so slightly as soon as the driver comes off throttle, and constantly changing its angle of attack through a corner. As IndyCar driver JR Hildebrand explained in his first track test with the Senna, the car's active aero and hydraulic damping work together to improve handling.
With the Senna, McLaren is blazing into uncharted territory. And just watching the rear wing at work is a damn good reminder.