Moodkit

This iPhone app is based on CBT. It has many features. But the most useful feature for me is something called "Thought Checker". Suppose in a certain situation you felt a surge of negative emotions. Then into the app you first describe the situation. Then you choose, from a large list, some of the emotions you experienced and rate their intensity. Then you describe the thoughts that ran through your head. You then select from a list of cognitive distortions, the distortions that would apply to the thoughts you just described. Then you write a new, clearer way to think about the same situation but without the distortions. Then finally your re-rate the intensity of the emotions you listed. Almost always it attenuates significantly.

I have found this to be an excellent way to defuse extreme emotions. For example, sometimes a single negative thought about my career or relationship status would ruin the productivity of an entire day for me. No longer. Repeated use might make the whole procedure automatic in your brain.

The other features are tips and advice to improve mood. You can commit to taking specific actions and check back. You can track your mood as a function of time. There are also journaling templates which are very handy. All in all, easily worth the $5 price tag. Drawback: you need an iPhone or iPad.