Fiat has MultiAir which is a mechanical valve train with variable hydraulic bleed-off on the intake valves. They claim some decent performance gains (all Fiat jokes aside).

Good video here.

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma