[tjbiddle]

Could come up with a thousand reasons, but if you want a quick "Fun" reason and a quick "Utilitarian" reason:

Fun: I travel a ton, I love looking at where I went to relive the experience. Especially if it was a recent travel and I'm showing things off to friends asking about it. I just open up the Timeline and say "Okay, well this day we flew in - then we took a 4 hour car ride, then we hung in this town for a few days, then took a boat to this island for some camping, then flew over to this city for a week, and..."

Utilitarian: As a US Citizen living abroad, I apply for the FEIE tax exemption every year to help me keep my first ~$120k as untaxed from the Feds (Should be my entire income, but no - US needs to tax on citizenship and not residency like nearly everyone else.. but I digress). For this rule, I need to have full 24-hour days in foreign territory, so for my documentation to ensure I'm still within my limit, I like pulling up Timeline - snapping a screenshot/export and saving it for later should I ever be audited.