CorBlimeyLimey,
While researching the answer to your question, I found out the one I tried was: TreeWorks 1.0 for SolidWorks by The Delta Group Ltd.
I was trying to build a Bill of Material in picture form, such as a tree. With the top level bill at top of tree or on left would be OK. Then the next level assembly below that, without any part levels showing.
Thanks for letting us know about Treehouse. A star for you.
Standing
SolidWorks Pro 2009 x64, SP3.0, PDMWorks Workgroup, SolidWorks BOM,
HP xw8600, 64-bit Windows Vista Business, Service Pack 1
Intel Xeon CPU, 3.00 GHz, 16 GB RAM, Virtual memory 166682 MB, nVidia Quadro FX 4600