Ruby´s Feline Hyperesthesia
She has an episode about once a day, or every other day. Some cats are treated for this condition (called Feline Hyperesthesia) with anti-epileptic medication, but in Ruby´s case I don´t think it´s warranted because the attacks are relatively mild, short lived and don´t happen all of the time…
Click here to find out more about feline hyperesthesia on Wikipedia