The next time you call a credit card issuer to complain about something you might want to turn up the heat with a bit more emotion. A new technology enables a call monitoring system to issue an alert to call center managers when the customer's voice hits a certain decibel level, uses harsh or foul language, or the name of a competitor. NICE Systems' "Emotion Detection" technology digitizes and stores angry calls on a server, where it can be batched with other angry calls, searched by keyword and emailed as a sound file among company managers.