I recently heard an interesting talk by Russell Foster, who tries to give a short answer to the question "Why do we sleep?". If we consider that we spend 36% of our life asleep, it is quite astonishing how little most of us actually care about sleep. Nowadays the world is constantly running faster and faster. The Internet conquered our lives, not only at work but also at home and it never sleeps. More and more people have the deep feeling, that they don't have enough time to do everything they want and what needs to be done. (Not being aware how much time they are wasting on stupid things, but that is another story.) So that is why people also tend to consider sleep as a waste of time. But is it a good idea to think like that, to only sleep 4 hours a night and to keep awake during the day with the help of caffeine in whatever form provided?
So listen to Russell's 20-minutes talk and it might open your eyes about how important sleep is.