I've been waking up at 5am for the past three years. I found that, by 9am when my colleagues started arriving at work, I had already managed to finish a large chunk of the work I had planned for that day.
I tend to do the actual work during these hours and reply to emails later on in the day. This helps me stay focused and I found it to be quite productive.
I don't drink coffee though, I have never felt the need for it.
The Leaks inspector is also way off sometimes. I spent a couple of hours hunting for a leak that was nowhere near what it was pointing to.