Okay, we've all done it. Changed lanes without a signal, pulled out in front of someone, caused someone else to make an evasive manuver or the like. What usually infuriates drivers that are already ticked off at you is your total lack of acknowledgement of your dirty deed. Most people are forgiving by nature.
Nobody wants to have an accident.
We all know that there are lots of crazies out there. As the traffic congestion continually increases around your area, remember to take care of one another. A little wave doesn't cost you anything and really helps recipients.