I built my whole company around this idea. For years, I was the front line support - IMO, its the best thing you can do to improve not only your product but your approach to life. That and having kids.
How did having kids improve your approach to life? (This is for my own comparisons sake since having a kid also changed my life and how I think)
One thing I always liked to do now is imagine the person who's angry or annoying me is just a 2 or 3 year old. It's much more fun and takes the edge off the situation whatever it might be...