Imagine if you had a heart-rate monitor and a sleep monitor. The heart rate monitor would know when you spiked yourself with caffeine, combined with the sleep

Imagine if you had a heart-rate monitor and a sleep monitor. The heart rate monitor would know when you spiked yourself with caffeine, combined with the sleep monitor that knows you've only slept 4 hours the past 3 nights. An alert pops up on your computer: "hey, you need rest. Stop drinking so much caffeine. Eat an apple and take a 20 minute nap, you'll feel better." Those are just two data sources. Harvest (time tracking) + RescueTime (productivity) + Runkeeper would be super valuable too. You'd know that you're 10% more productive on days that you run.