At Tue, 22 Nov 2011 11:40:35 -0800,
Dave Abrahams wrote:
> 
> 
> I often discover that I completed something a few days ago and I would
> like to mark it done with the appropriate date as though I had marked it
> done in the past.  That means, e.g., for a repeating event it might
> repeat sooner than if it had been done today.  Is there a way?

M-x org-todo-yesterday ?

If there is a way to do this for days further in the past, I would
welcome it! I also find myself wanting to do this often. Right now I
just mark it done, then manually adjust the log entries.

best, Erik