Inspired by this thread and your post, I decided yesterday to try at least a 24 hour fast. After a breakfast shake yesterday, I played tennis and went about my normal activities. I eat a fairly ketogenic diet, so the hunger wasn't too distracting, although I felt very laid back in the evening.

This morning, I woke up about an hour earlier than usual with a great feeling of energy and focus. No real hunger. I'm going to push it a little further as long as I feel good. Thanks.