Steve Pavlina posted a very interesting article a few weeks ago about complaining.
What this article really challenged me to think about was the link between complaining and responsibility.
When you complain about something it is like acknowledging that someone or something else is responsible for you and how you feel. If you complain you are saying "I have no power over this situation, but I wish it would change". In the real world significant change in your situation only comes about by your direct action, therefore anything you do otherwise is giving up control over your life.
When you say to yourself that something is outside of your control it is a great excuse to make no effort to change. Only when you accept responsibility for something will you feel compelled to take action to change something if you do not like it.
Complaining is the exact opposite of taking control of a situation. The more you do it the less control you have, over that situation and your life.