Our little family moved into our current neighborhood a few years ago, and it was a new neighborhood, so we got to see all of the other houses go up about the same time as ours.  Shortly after we moved in, the neighbors to the back began to build their home, and since our house is a two story house, we could sit and watch out the back window everything that was going on. 
An older couple moved into the house and proceeded to turn their backyard into a very beautiful place to sit and enjoy the cool evenings. 
To add more life, they added bird feeders.  And then more bird feeders, and after that, they added a few more.
Consequently, this corner of the neighborhood seems like a set from an Alfred Hitchcock movie because of the many avian visitors.  At first, I was kind of perturbed, because of all of the droppings, etc. everywhere.  But, I have to admit that due to the crowd of birds that they have brought in, I am always fascinated with just watching all the life in our own backyard.  We also have birds nesting in our front yard each year which is so interesting to watch from my office window.  So much can be learned from just watching nature.
Nevertheless, even though I don't know my back neighbors well, I decided to paint them this envelope with a note tucked inside to thank them for the birds they have brought into the neighborhood.  It's funny the positive impact you can make on others as you try to make your own little corner of the world a pleasant place.

This was done in gouache and a little pen and ink: