1. Walking out of your house on an average day (morning)
Not really a problem unless I have the misfortune of having to walk by one of the resident backwards-cap-wearing, pickup-driving frat boy (or sorority girl) types in my apartment complex. In that case, I fix my eyes on something, anything, off in the distance and pretend they don't exist as I walk by, all the while just
knowing they're thinking "WTF is this joke doing here? Is he even old enough to be in college?"
2. Having the person sitting next to you on the bus start a conversation
I'd probably be either annoyed, intimidated, or both, depending upon who it is and what they say. I'd politely respond to whatever questions they ask me, and it'd quickly become rather obvious that I'm not interested in continuing the conversation.
3. Being yelled at by a superior (work or school) for something you did wrong
No doubt, I'd turn bright red and start struggling to find words to respond, particularly if others were around.
4. Giving a presentation in front of coworkers/classmates
Disproportionate nervousness in the hour or so leading up to the presentation. While sitting in class awaiting the big moment, I typically have to keep tapping my foot or something like that to hide the fact that I'd be shaking if I tried to sit still. While up in front of the class, I can do OK and show only minimal nervousness if I don't have to look at everyone - but as soon as try to, my face goes bright red, my eyes dart off to the corner of the room, and it's all downhill from there. I've never really had a huge meltdown or disaster during a presentation (partially because I haven't had to do many in the major I chose), but at the same time, I know that it becomes quite obvious to everyone watching that my nervousness goes well beyond the typical, mild form that a lot of people experience - and the embarrassment resulting from that causes a vicious cycle of increasing self-consciousness until I finish.
5. Asking a stranger for directions
Probably wouldn't happen unless I'd exhausted ALL other options, and probably wasted an excessive amount of time in the process of doing so.
6. Seeing a person you kinda know walk towards you on the street
I'd probably wait too long to make sure it was them before acknowledging them, partially thanks to my crappy vision and the fact that I won't wear my glasses most of the time. If it's someone I just barely know from class or something along those lines - particularly if it's a girl - I'd feel trapped, knowing that if I ignore them I'll come off as rude (and possibly get called out for it), yet also feeling I'm so pathetic that they just might prefer me to spare them the embarrassment of stopping to talk to them in front of others. I also feel very "caught off guard" when this situation arises, because if I'm out by myself shopping or whatever, I tend to start thinking about other things and become very detached from my surroundings.
7. Asking a teacher for help with something
Much like the stranger and directions, this is a last resort. I particularly hate going up to ask a professor a question during a test, and when I do, I worry greatly whether I'll end up being either too loud (and distracting others taking the test) or too quiet (such that the professor can't even hear my question).
FWIW, I just graduated from a four-year B.S. program this month, and had to take quite a few difficult math/science courses over that time period - I can count on both hands the number of times I ever went to office hours, thanks to my SA.
8. Talking to your family
Not really a problem within my immediate family, but for my extended family, it's quite a chore. They're not very understanding of my SA for the most part, and the ones who are semi-aware of it are extremely patronizing about it, even if they mean well.