We all know that one person you needs to be the center of attention. When we relate that back to Inventor we could always display the Center of Gravity (COG) and receive X,Y,Z, but not much more. With 2009 Inventor we have some long awaited abilities to utilize the COG. The COG glyph now displays in a part or assembly model with three planes and a point. You can select the planes or point when measuring from an object to the center of gravity. To select the planes or center point, Selection Priority must be set to Feature Priority or lower. You can also resize the planes of the glyph to better match your visual and selection requirements.
To identify and document the center of gravity location in a drawing view, you can select to have a center mark display at the current calculated center of gravity for the model. The center mark's location is associative to the model and you can add annotation to the center mark. In the past you may have done this with adding a sketch point or something else to represent the COG.