Today, I was pleasantly surprised when I tried the -PURGE command in Civil 3D 2010. While attempting to fix a corrupt drawing that was sent to me, I used this command and found a couple of extra options that I had never seen before (see image below). So I tried the "Zero-length geometry" and "Empty text objects" on the drawing and sure enough it reported that it had in fact removed several such items.
My first thought was, I have to remember to use this on all drawings, one never knows what we have inherited.
Be Better! ...Clean thoroughly.