An "All in one"
A recent idea I've had is to incorporate the well wishes usually written in a card on the rear of my paintings.
It's a nice touch and this could be done for any presentation - be it a retirement, birthday or other special occasion.
You would never need worry about where you put your leaving card again - it's on the back of your masterpiece.
The back of your picture now has another purpose other than holding your painting in the frame!