Flight price variation (n=1)
I flew from Gatwick to Edinburgh for a friend's wedding, and had Skyscanner tracking ticket prices for me. It continued to do so long after I bought tickets, but I figured it'd be fun to extract the emails and plot the change in price over time.
It did what you probably expected: bobbled along until close to the date.
The flight itself was busy, but not full. I'd say there was a seat free every other row.