We've had a lot of clamor to give EOTD honors to VW's innovative VR6, but the whole concept just got so much cooler when those mad scientists in Wolfsburg put two VR banks per engine.

Sure, Lancia got the jump on making mass-produced insanely-narrow-angle V engines for cars, but did they ever make a W16? After VW started dropping VR6s into engine bays in 1991, the maniacal laughter commenced issuing from their workshops. Why not make a V engine out of two V engines? Good idea! In 2001, the VW Passat got a W8 and the Audi A8 got a W12. The Phaeton and Tuareg received W12 powerplants, as did Bentleys and Spykers. And, of course, we mustn't forget the Bugatti Veyron, which looks down on those lowly 8s and 12s from the heights of W16 godhood. It's true that the W8, W12, and W16 (not to mention the triple-banked W18 VW used in some late-90s concept Bugattis) differ enough from one another to be considered separate engine families, but they share enough genetic material that we're lumping them together for EOTD purposes. Thanks to Dearthair for the suggestion!
[Volkswagen W Engine Study Guide (PDF), Autozine Technical School]