Our mutual friend (who you and Linda will meet in person in March) has spontaneously started RAOSK (Random Acts Of Senseless Kindness) wherein she selects five friends at random (preferably someone you don't normally acknowledge) then sends each of the five a small gift or a greeting card to let them know that they are loved and not forgotten.
The idea is to incite those five recipients to do the same thing. Eventually everyone will be loved and recognized.
This would be repeated several times each year, not simply at designated "occasions".
The only thing that I would add...the sender would not sign or otherwise identify him/herself.