Itchy feet is a good exercise to do during the day if you work in an office and get back pain after long hours in front of the computer and need to stretch your back.
Lean forward and hold on to your left foot with your right hand. Gently pull your arm towards you to stretch the right side of your back. Keep the stretch for the desired amount of times before switching side.
An alternative is to hold on to both ankels at the same time and push your back up. This is similar to a cat pose in yoga and will stretch the middle of your back.
This exercise is just as well suited to do on an office chair as on on the toilet.