Hehe, I can say I've only been asked this a couple times in the past.

>Do you pee standing up or sitting down? And if you're post-op, which did you prefer in the past?

I am pre-op and I've pretty much peed sitting down for a while now. Sitting is easier, just have to make sure nothing dribbled onto the seat. :)

I will admit once in a blue moon get that 'fuck it' attitude and stand. But that's pretty rare.

I would add that while I have absolutely no problem answering this, other transpeople may not care to.