assign blocks to regions from within a node edit form

I'm wondering if someone has done this before.

I would like to be able to assign a block to a region from within the node edit form.
I want to allow some content editors to assign these blocks on a per node basis, but i don't want to give them access to the blocks config page.

Something along the lines of the cck block reference module, but the ability to specify the region and weight for display.
if the block is referenced from within the node, it would override any display settings for that block on the node config form.

any suggestions?