Having worked hard to get Nathan to understand what is and isn't a socially appropriate reaction to frustration or upset (telling your feelings is good, yelling and hitting people, not so much) we are now starting to work on getting him to understand that there are consequences to his choices. I.e., if you choose to threaten your brother with bodily harm for having touched the computer, you may lose computer time.
Yesterday, he yelled at his teacher for asking him to put his agenda in his bag. She told him that it was not okay to talk to people like that and when he continued to refuse, he lost his art time privileges. (He brought the project home to finish.)
I think this was a good balance. Yelling at people to get what you want is not a good strategy (although I have met a number of adults who never learned that lesson). If you yell, people are less likely to cooperate and could start to actively work against you. In the end, it was a minor blip and it got a minor consequence.
It's hard to balance out because I do want him to respect and understand his feelings. I don't want him squashing what he feels down and putting on a pleasant expression because his feelings might make other people uncomfortable. But there is an appropriate way and an inappropriate way to express those feelings. I'm still working out how to get both messages across.