I am continuing to migrate my old project repositories from CVS to svn. In the process, today, I found some old code I wrote in 2001 (or earlier) to generate input files for daVinci, an old di-graph visualization package. It turns out that daVinci has been renamed to uGraph, so when I released the code I updated the module name.
There are now other, possibly better, graph visualization tools available. NetworkX looks very promising. It uses Graphviz, which produces some really nice output. But, daVinci was the first tool I used for doing relationship analysis. I used it to analyze calls between functions in some nasty Perl code I was maintaining. I also used it to analyze the module linkage dependencies in a large C toolkit library, with the idea that we would split the big library up into several smaller .so files for release. And there have been several one-off projects along the way, too. Unfortunately, I seem to have lost most of that code.