Internally, we have a graph editing tool which uses D3 (screenshot [1]) which I threw together based on some existing examples. I'd be happy to open up the sour

Internally, we have a graph editing tool which uses D3 (screenshot [1]) which I threw together based on some existing examples. I'd be happy to open up the source code if there was any interest, though it's really nothing all that special. The layout algorithm could definitely use some work for our use-case at least. It's force-directed at the moment, using stock D3 layouts, but really needs a hierarchical mode. While it's not perfect, it is intuitive enough that non-technical people "get it". Beyond this, yEd[2] is really quite cool (even if it does have a very dated UI). [1] https://www.evernote.com/shard/s3/sh/67c67a48-8b3d-4eac-b7ee-427fbf6fb5ca/ab7dff4c05a5503d06b001ac7f248451/deep/0/Define-concept-relationships.png https://www.evernote.com/shard/s3/sh/67c67a48-8b3d-4eac-b7ee... [2] http://www.yworks.com/en/products_yed_about.html http://www.yworks.com/en/products_yed_about.html