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.