VTEC basically gives you two completely independent cam grinds to choose from on the fly. Porsche has a "Vario-Cam Plus" system that pretty much does the same thing, lets you pick one of two cam grinds on the fly. Porsche's system lets you also adjust the cam timing (or at least phasing, the timing relative to the other camshaft) while I'm not sure if VTEC lets you vary that or not.
Most manufacturers have variable-valve-timing mechanisms available on at least some of their engines. At least some have mechanisms that also can vary the lift, either by choosing a specific cam grind, or in an arbitrary manner.
-soD
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