Idunno, when I wrote that I thought of someone trying as hard as possible to become a walking god.
Sooooo.... A gamer longing for infinite power? Power gamer.

Yeah, that's how I understand its typical usage.
Ppl who min-max & only use the most powerful gear every time...and who's main goal seems to be seeing how fast & awesomely they can kill the bosses/defeat the game so they can LULZ about it. Or something. Not that non-'power gamers' don't do some of that stuff too. It's just...a sort of attitude sometimes I think. (edit: there's a wiki entry for it, lol http://en.wikipedia.org/wiki/Powergaming )
I don't like to purposely gimp myself much, but I don't mind a little. Usually tho if I run around with nothing but the 9mm it's more because I'm just curious to
see if I can. Because it is there. That sort of thing.
Games should become more savvy with player-set difficulty customization. The Easy/Normal/Hard 3-choice model should be tossed out the window, imo. It's never been great (since someone's Easy is someone else's Very Hard) to begin with.