Great thread!
I've never really had many negative issues while moving through life as a masculine woman... I'm comfortable with who I am and confident in all aspects of my life, and have been extremely lucky to have such a supportive family.
I have also had two careers where being masculine in appearance and dominant in personality has been to my advantage, and I know I'm lucky in this respect as well. Being sturdily built has also benefitted me.
It's appalling to me that my butch comrades have endured such treatment at the hands of ignorant fuckers! Knowing myself, I probably wouldn't have handled someone getting physical with me in as civilized a manner as those who have posted above.
Sadly, I have to say the most discrimination I've witnessed as a butch has been within the lesbian community. Butches, because of our outward appearance, got the shit kicked out of us in the past (Some still do, clearly.) and really paved the way for our community, only to now be seen as some sort of sub-culture.