Don't get angry... get even ;-)
Angre is a sign of weakness. Never ever get angry...
I don't mean literly 'never get angry'... it's normal to get angry sometimes and supressing it is probably not a good idea! What i mean is get angry, get pissed if you want, just don't 'freak out', don't start yelling screaming, insulting etc. Keep your cool on the outside. It's fine if people see that you are angry, just let it be a passive/agressive kind of angry...
When i get angry at a woman she definitly notices it, i get a sly grin and just set up the stage for some verbal ownage. Keep strong eyecontact, don't blink, shoot em down with your eyes. If it's a guy and he gets me really PISSED i'll just start challenging him a bit and annoying him. Never strike first, again sign of weakness PLUS it can get you in to a lot of trouble with the law! Let em talk sh!t, just keep owning them verbally and put on your 'evil genious' face. If they start getting really pissed and a bit physical than just start daring them a bit... poke em in the ribs, step on their shoes, pet them on the head... whatever, just make it subtle...
I've gotten a number of reactions when things got up to this point. Either they start pushing and their friends pull them off almost instantly, they then end up yelling from across the room a bit more at my backside... They just get pissed, make some lame threat and then walk off... finally they actually have a go at me (pretty rare).
So, basically, don't freak out, if you get angry just start verbal ownage and challenging them...
You might like it better to just ignore them and dismiss your angre. Whatever, you have to decide for yourself. I noticed for myself that when i do this i catch myself later feeling bad for "backing off"... so i don't do it anymore... whatever works for you!