Challenge
Write a letter to your past self.
It can be a letter to your one-week ago self, one-year ago self, or maybe even your childhood self. You can offer them advice, warnings, information, or even false reassurances -- whatever you'd like.
To myself, 4 seconds ago
Hey,
Read this quickly because there isn't a whole lot of time. Most importantly, you should really stop walking to read this because bad things can happen when you're walking without paying attention. Please look up and notice the coffee table in front of you a little to the left. Now pay attention to your feet. You are four seconds from catastrophe. If you would kindly step slightly right as to avoid the very painful crash of your toe into the bottom corner of that wooden table.
Yeah, I stubbed my toe. It really hurt. Save yourself.
You're welcome,
Your future self