JEALOUSY- The Worst Feeling in the World (Or at least one of them)

What is it about jealousy that we hate almost as much as embarrassment? That burning envy we have for what we don't or can't have. It's one of the worst feelings of the world, and it drives us to do things that most people would never do rationally. The only way to really get rid of it is to ignore it or remove yourself from the situation.
What does jealousy really feel like though? For me, it's a burning feeling for something I don't have. It's usually got anger or sadness mixed in, depending on the reasons for being jealous. Seeing someone with more can also drive me to try and do better so I can have what they have though, so sometimes it can work for good. But often it brings me irritation and anger to the world in general.
Thoughts? What does jealousy feel like for you?