Thanks to everyone for their latest replies.
First, everything makes me angry. Everything. I have been to therapy in the past and have practiced some cognitive-behavioral techniques over the last year. I can now look back at my anger episodes and coherently describe the limited thinking patterns that created the anger responses. I appreciate that, and will continue to practice the exercises and utilize the concepts in my self-analyses, but I haven't seen any positive changes in my anger responses. They remain irrational and, until I simmer down, the voice of reason that tries to explain them away is treated as an intruder and a potential source of additional anger.
Unfortunately, there is no great, unifying trauma to explain my rage. I was raised by an angry but loving mother, was miserable in high school, dated the wrong girls until I found the right one, and am now very conscious of how lucky I am to have a relatively fulfilling, low-stress job, a good dog, a great wife, and an indescribably awesome daughter. And I am angry at one or more of them on a daily basis. I suppress the fury I feel when, for example, my daughter throws a tantrum -- at least until I can exit the room -- but for how long? She is learning something new each day and what a horrible thing it would be for her to learn my primary approach to problem-solving! (which, incidentally, is nearly identical to her current approach....Yup, I'm an emotional toddler.)
Meditation seems like a remarkably rigorous approach to taking control of one's emotions. I'm hoping to receive encouragement from respondents who have had success with that approach, whatever the tradition. I know that everyone is different, and that these things take time, but following an anger episode this morning where my yoga/meditation was interrupted, I feel hopeless. I also wonder if people who haven't experienced habitual anger can entirely understand what I am describing. I wish I could just "man up" or "get a grip," but that hasn't worked.
Anyway, any/all personal experiences are appreciated and I will take the time to look into/consider any suggestions I receive.