It's a couple summers ago, at the height of the summer tourist season and I'm cycling up 4th ave SW in DC. Somewhere between the NASA HQ and the National Mall my camera bag - packed full with a fairly new DSLR, a few lenses, and a secondary cell phone - came unbuckled from my messenger bag and tumbled to the sidewalk. Probably a few thousand dollars of gear, not counting the considerable hassle of resetting 2fa and credentials for every possible account that could be tied to my phone (it was password-locked but I have no idea how well that would survive a determined attack).
I was booking it pretty hard trying to catch a metro, so I didn't notice the loss for a couple more blocks. After the only genuinely involuntary (and painful!) facepalm I've ever given myself, I hurried back home (lived in town close by) and immediately started cancelling every account when my main cell phone rang. The bag was waiting for me, all contents undisturbed and intact, in a hotel lobby a couple blocks away. An anonymous samaritan had picked it up, brought it in and gave it to the concierge without a word, then walked away. Concierge called me using my contact info in a business card that was also in the bag.
In one instant, some unsung karmic superhero single-handedly erased the work of several hundred asshole double parking jobs.