Sometimes, I wonder why God didn't list the Ten Commandments in reverse order, since the 10th commandment correlates to the first sin - desire. Eve's sin wasn't simply her desire for a piece of fruit; it was the desire for knowledge that Satan told her would make her like God (Gen. 3:5). Eve's covetousness caused her to violate both the first and tenth commands that God later gave to Moses.
When we don't covet, we pretty much eliminate our reasons to disobey the other commands. Wanting what isn't ours causes us to lie, steal, commit adultery, murder and refuse to honor our parents. We refuse to rest because we can't get what we want in 6 days of work. We misuse God's name when we use it to justify something that we want to do. We make gods out of wealth and relationships because we don't want to have to put all our trust in God.
I have a hard time coming up with sins that don't involve some form of covetousness. Yet because it's the last in the list, we tend to think of it as being the least important. But it's not. When we stop sin while it is still in our hearts and heads, we avoid making others the victim of our sin, and we avoid many of the serious consequences of sin. Contentment is realizing that God has already given me all I need. Just remember that God's gifts to you were designed for you and you alone.