Hi, 
I was driving to work this morning and the car started juddering violently when I hit 60.  There was also a lot of noise, and the car behind me flashed me as if there was something visibly wrong.  I couldn't tell whether the noise was from the fromt or the rear, but it was pretty loud.
I limped to work at 50mph, and the vibration was only just noticable.  I would love it to be a weight that has departed a wheel, but fear that would be too simple (and cheap).
Any ideas?  I will have to leave it at the mechanics tonight, I cannot drive a 40 mile commute in it in that state.
Cheers
James