Do you want a niche cut out of your wall for a soap dish or other amenity?
Draw a wall in plan view. Goto Tools... Edit Cut Profile. Select the wall in plan view. Now sketch a shape for your cut (like you would the Split Face Tool) Finish sketch and you'll notice the shape of the wall was cut. While in edit mode a blue arrow controls which side you want to keep.
This tool works in Plan, Section, and RCP views. This tool is view specific (ie. Any niche you cut out of your wall using this tool won't show in any other view.)