Ed's too modest to post these links himself - but all spiders wobble - including all four of mine. Three of mine are full siblings to the striped girl in the first video and my fourth is a 1/2 sib to them. The "trainwreck" that he describes in one of the videos is my Tonka. Tonka no longer spins - he has a very slight head wobble, similar to a Parkinson's shake.

All of my spider's wobble display as a very slight shake or "vibrating" of the head that Ed shows in his video.

YouTube - Understanding the Spider Wobble

YouTube - Spider Wobble part II