On Tue, 17 Aug 2010 13:34:32 -0700, Michael Hoffman <9qobl2n02@sneakemail.com> wrote:
> 
> I have happily been using org-mode for many years to keep a todo
> list. I like keeping a log of the actions I've completed, but I don't
> like them in the same file taking up space. Previously I have moved
> completed TODO items and checkboxes to another log file manually. Is
> there a good way of doing this automatically? Do you have any other
> suggestions for how to keep a log of done tasks while removing the
> cruft left over from the current list?
> 
> Michael Hoffman
> 
> 
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Check out the Archiving section in the org info manual.  It does
exactly what you want.