I've known about Quantified Self for years, but never actually started any project.
I'd like to track what factors cause me being with a runny nose sometimes.
In my history I passed through years of really bad allergy, that lasted entire seasons non-stop.
I think that was linked to hormonal changes during growth, because that's a thing of the past now.
However sometimes I find myself with the same symptoms every now and then and I'd like to spot the causes.
My main suspects are alcohol consumption and late go-to-sleep time; as expected, they often appear together, so it's not clear which one of them is the main culprit.