In reply to Christina Hendricks.

Hi Christina,
Thanks.
How do you get a widget to just show up on one post?
That is the kludgy bit. The post needs a unique category and I use the jetpack feature that lets you add a widget to a particular page or category or tag. This is not ideal, as you need tons of categories and your widget editor get confusing. I am asking for the ‘display_posts’ plugin over here.