I'll toss in my setup too, which I started semi-recently and has been working well:

In my .bash_profile I essentially just `open --background -e "...$(date +%F).txt" &`.

Since I'm in the CLI daily for work, I get day-stamped files passively opened without having to think about it. It's a nice quiet reminder to keep notes throughout the day, and it all just goes into a folder in dropbox that I can trivially `grep` or add with other tools or add side-files (typically "date - stuff.ext" so they appear next to the day's notes).