Photoshop for Creative Cloud includes an update to the Pen Tool (update released in December 2012). This update enables the anchor point of a pen tool to be moved by using the space bar when the anchor point is active.
In this example the Pen tool (marked with a red square) is used to create path A, and with the pen tool still enabled on the anchor point (i.e. the mouse or pen (like a Wacom Cintiq or Intuos tablet pen) rightclick not released) and the Space Bar pressed, the anchor point that has been placed will move to where you need it to be.
This is enhancement is great for when a path is first created and being created. However, if you have already laid a path down, then re-select an anchor point using the ALT key and press the space bar as soon as the anchor point is engaged, the path will then move to the new location. You are also able to use the handles for the anchor point to preserve any curves that you have enabled.
In the following example the curve has two handles, where the anchor point is marking the curve intersection.
Selecting the main anchor point using the ALT key will collapse the curves into a point
In this case, use the SPACE bar over a handle and the whole curve will move
This enhancement will enable you to work very quickly when using the Pen Tool in Photoshop CC, without having to undo and lay down a new path.