I now have a wall like this in my office, though much more spare at the present. I just print out inspirational quotes and pretty things, dig up old photograph, or ripe out pages in magazines and tape them up on the wall.
Hanging Photo Album - 12 Ways to Use Your Christmas Lights in the Summer - Southernliving. Clip all your summer pictures up on strings of Christmas lights for an ethereal glow in your room. Swap the pictures out next season, and keep making memories.