Interesting thread in that it presumes people have something to be angry about - not a presumption I would make. Call me a Pollyanna, but I presume most people have far more reasons to be happy than angry.
Sure, we all have moments of righteous anger, and should deal with the situations that cause them, but deliberately stoking personal fires of anger, disappointment, thwarted expectations or resentment? That path seems to be a self-fulfilling prophecy. The madder you choose to be, the more reasons you find to be annoyed. Conversely, the happier you are, the more reasons you find to be happy.
So to answer the question, what am I angry about today? Absolutely nothing.