I'm very analogue, so I like to write postcards to my friends.
In 2004, I was standing at the train station in Paris on my way home and realized that I would see my friends again in the evening, while the postcards would at best arrive the next day.
So I looked up the addresses of two completely unknown people whose only common denominator is the wonderful surname Sörensen - and simply wrote both of them a friendly postcard as if we had known each other forever.
This spontaneous action first became a fun repetition, then an interesting challenge and finally my second nature while traveling as well as a nice documentation for myself (although unfortunately some cards got lost).
I imagine that the two of them are just as happy about a new card as I am when I write it.