What do you believe about karma?

I have always wanted to way in on this question.  I one sense I do believe in karma.  The energy you put out in this world will return to you generally speaking.  If I am nice to my neighbor he will be nice to me.   If I am kind generally speaking others will be kind to me.  So also I have expereinced how hurting others will  bring bad karma to you.  Case in point was when a friend of mine was fired from her job by a hr committe that used some very underhanded  techniques to do so.  They also did everything in their power to restrict her earnings while under severance.   Within a months time every person on that committe had a tradgedy in their familly, shocking deaths, children with surgery, and illness.    this all said I have a problem with the karma idea.  I grew up in a fundementalist home where you were supposed to do right so God wouldn't be upset with you and punish you.  I hear people especially kids who talk about doing good so others will do good to them.  I think more important than what you do is with what spirit and reason one does it. 
Tim