Middle names

I was talking with some colleagues and the topic of names came up. It got me thinking about the purpose of middle names. While some cultures seem to inherit middle names from their parents, others are given in honor of close relatives. I dont have a middle name though both of my parents do. Interestingly, their middle names seem completely random. Do you have a middle name, if so, how did you get it? What are your thoughts on middle names in general?