...until I became involved in the online planner community. This is an actual thing and Facebook groups, forums, blogs are dedicated to organising groups of people who send little parcels, or happy mail, to each other!
I'm a member of one group on facebook which is run solely for this purpose and a few others where it's not the sole purpose of the group but people are so generous and kind so you have the option of putting your address on a spreadsheet/document to indicate that you're happy to give and receive parcels of joy.
I've RAK'd and been RAK'd several times this year, and it's always a lovely surprise. I tend to send things that I no longer need or think someone would get more use out of, particularly filofax inserts, stickers (I'm just not that type of person it turns out), samples of patterned or washi tape, all sorts. Mostly stationery but I'm hoping as I get more accomplished with my creative creations I can expand to sending mail art.
Photos below of some of the happy mail I've sent and received!