I abandon half-composed postings regularly. However, they are saved as drafts.
I was trying all sorts of way to clear my drafts -- like saving an empty comment (doesn't work), replacing it with a single 'a' (works).
And I was quite surprised that the drafts are saved on the server. I could see them on different computers. This can be good or bad, so no comment.
Finally, I discovered My Drafts on the right-hand navigation bar!
But, I would like to ask if we can have a 'Clear Draft' link after the comment box?