P v P : How to deal against void rays?

Agreed chowzilla, actually, in a 1v1 Thors get beaten easily by VRs, but in a 4v4 i played a player massed Thors to the tens, while an opponent got about twenty VRs, he then charged up on anothers base, so they all had full charge and he had a destroyed commancenter, but then the Thors came.

The splash annihalted them, with not even one Thor destroyed.
VR rushes are mostly good against: Mass marauder/mech mainly armies, zerg that techs to little or a protoss that somehow does not have enough stalkers, sentries and phoenixes.