From Tejvan Pettinger at PickTheBrain.com:
It is an oft repeated axiom that money cannot buy happiness. While this is certainly true, poverty will not buy happiness either. Some people become very wealthy, yet struggle to enjoy their lives. On the other hand, others manage to go through life with very few money problems simply because they are able to make the most of what they have. Ideally you should try to combine both prosperity and happiness. To do this I recommend the following steps:
1. Learn to Value Simplicity. The aim of life should not be to accumulate as many possessions and as much wealth as possible. We should learn to be content with what we have and appreciate the benefits of simplicity. For example, if we clear out our unnecessary clutter we will achieve a greater feeling of space and freedom.
If you feel happiness is directly related to material possessions, you are making a mistake. Happiness can be gained just through being content with a small amount of possessions. Our inner wealth is not just about what we have, but what we are content to live without.
Read more here.