Eh, not really- it's rare for a game to grab me enough for me to even want to put in the kind of time needed to gain mastery. Often the games I put the most time into are RPGs... and let's face it, you don't really 'master' an RPG becuase the point is the story & the grind is simple enough. I mean, there's mechanics to get good at, but not really any opportunity for finely honed twitch motor skills to kick in.
I did beat (mostly) all 3 of the Ouendan/Elite Beat Agent games on all difficulties. Technically I have 1 song left on Ouendan 2, but one day I'll sit down & get it done.
I also experienced a brief window as a savant of Columns on Genesis. Had it as a kid, wasn't any good, might get past level 10ish once in awhile. Came back to it in my late teens/early 20s... I don't know how it happened, but I regularly pushed level 70+ for months. There was no lead-up either, it was immediate- and kind of weird to experience, quite frankly. Then I put it away for a bit & lost it- these days I tend to hover in the 20-30 range. Although it's been awhile, maybe I should see if I can do the crazy stuff again.