Cold anger.

My temper is quick and in short flashes.
I get annoyed easily and then cool down just as easily. But this is only when it is an annoyance or a temporary matter that's being solved.
Sometimes, however, I express cold anger.
This is when I am immature, stubborn, childish, obstinate and mostly relentless in my display. This is the most passive-aggressive I can be, since I outright ignore the person I am angry with. Usually I tackle my problems head-on, but in these cases, they are pretty much dead to me.
It takes a lot to send me into a cold rage. Not a lot to get me out of it. Usually it's stuff that has been building up for a while, or something happened that was so incredibly wrong yet has gone un-apologized for.
I don't believe in forgive and forget. Although I may occasionally embrace the idea of one or the other, I have never believed in both together.
Should I let go of it? No.
It reminds me of what I value in people, and always serves to let me know that it's very important to practice what you preach. It teaches me to realize that people are not what they seem to be, and that people can also drastically change overnight.