Rotate

This tool rotates the selected UV components about the UV coordinate closest to the pointer. Click anywhere in the Texture view and drag horizontally.

Double-click on UV Points

You can double-click on UV points with the Move, Scale and Rotate tools and the following dialog window will open:

The point on which you clicked can then be repositioned numerically in UV space.

Active Tool manager options

The same options apply as for the move tool except that the point and edge snapping options have no effect.