Page 107 of the User Guide:
The Flip View command will change the current view by flipping the eyepoint to the other side of the view plane. Internally, the view normal changes the sign of its direction. For example, flipping the top view will yield the bottom view and flipping the front view will yield the back view.
The Rotate View command rotates the eye point 180 degrees about the up vector.
Try the Navigator, another undocumented feature. The Navigator does not officially exist. Open the shortcuts palette and set a shortcut key, I use an "n" as you can see in the screen shot. Close the shortcut menu and try it out.