If the office was like flickr, when you walked past that really pretty calendar in your co-worker's cube, you would stick a post-it note near it with a comment saying "Wow! Beautiful image!"
Your co-worker with the photo of his kittens on his desktop would have notes left on his desk letting him know just how cute those kitties really are. Some commenters would leave little photos of their own kittens along with their comments, hoping to draw people to their own cubes.
People would get flurries of praise on colorful little notes for having the most robust potted plants, or geeky compliments for having a bright red swingline stapler.
And people who got the most comments on their cubicle walls from passers-by would be so very proud.