[Lynk Former]

Even the manliest man of them all, Goku from Dragonball Z is played by the same chick through his childhood, into adulthood, into parenthood and through to the very end when he's a grandfather.

There are a tonne of male characters, both Japanese and English that have girls as voices for guys. Personally, in the case of FMA, I thought the English dub voices matched the majority of the characters more than the Japanese did because of that fact. The chick they got in to play Envy for the English version is brilliant since you can't place her as being male of female. It fits the character very well since Envy is a shape-shifter.

But when it comes to not knowing if they're male or female, the look is more disturbing than the sound. Just look at Final Fantasy. There aren't any actual males in it, just females and dickgirls with muscles and flatchests.