Wouldn’t it be great to have a time machine so you could travel back in time and relive your greatest experiences? I think today we can make this dream a reality. I’ve been tracking many aspects of my life over the last few years. My diet, my sleep, my activity, my exercise, my body metrics, my likes and dislikes, the music I listen to, my contacts, my conversations, my opinions, my mood, my air miles, my location, my energy levels, how I spend my money and how I spend my time, the hours I work and the time I spend in meetings, my browsing history, how often I stretch and how often I floss, how much alcohol I drink, the temperature indoors and out, the air quality in my bedroom, how much I feed the fish and the last time I changed the light bulbs … All this is recorded as data at varying levels of granularity, some of it by the minute.