A callgraph for C programs

I was playing with Egypt the other day. It's a very cool application. It'll generate a callgraph for your C programs, no more no less. Actually, doxygen (kind of) does that, but what I really liked about this application is its simplicity. From Egypt's page

Egypt neither analyzes source code nor lays out graphs. Instead, it leaves the source code analysis to GCC and the graph layout to Graphviz, both of which are better at their respective jobs than egypt itself could ever hope to be. Egypt is simply a very small Perl script that glues these existing tools together.

Code reuse at its best. Give it a try.