Multiple leader lines on one annotation (non feature-linked)

A very similar question was asked over at Ask A Cartographer and the answer was:

There's not even a hard way to do this yet. If you've got a lot of these, I would suggest making a line feature class and just add line features for the leaders. You'll have a lot more control over where the leaders meet the text as well.

There is also an ArcGIS Idea for Multi-leader-line balloon/callout boxes to which you could add your vote.

I do this all the time, using a rather crude workaround, but it works. I create multiple annotations on top of each other and point each to where I want leaders. I then tweak size and drawing order to make things look right. In the case of balloon callouts, I will create tiny polygons with no border that match the annotation background color to cover up unwanted annotation borders that cross over leaders.