Sometimes my anger, (sometimes I'd call it rage) is covering it up that I need to have a strong, long, good cry. One time with a therapist years ago, she had me beating a pillow to get some of my rage and anger out. I beat on the pillow some, then fell into a heap, curled up, sobbing my eyes out uncontrollably. Sometimes I feel that what is under the anger is still more anger though.
The main thing I do anymore is write in my journal about it. There is a lot of angry venting in my journals.
Here in my city have a business where people can go to break things, to get their stress and anger out. It appears to be quite a popular business too. You're not alone.