A new option has been added to the PURGE command in AutoCAD 2011, this is Purge Zero Length Geometry and Empty Text Objects. This new option deletes geometry of zero length (lines, arcs, polylines and so on) in non-block objects. Also, deletes mtext and text that contains only spaces (no text) in non-block objects. This can be useful when trying to tidy your drawing and remove empty text boxes etc, which you were perhaps not aware of.
Note: The PURGE command will not remove zero-length geometry or empty text and mtext objects from blocks or locked layers.