See also MacPorts
To quote the DarwinPorts FAQ:
DarwinPorts is probably best described by comparison: It's sort of like the FreeBSD ports collection or fink in that it automates the process of building 3rd party software for Mac OS X. It also tracks all dependency information for a given piece of software and knows how to make it build under Mac OS X and install it to a common location, meaning that software installed via DarwinPorts doesn't simply scatter itself all over the system or require user knowledge of what to install in what order.
DarwinPorts is written in Tcl! DarwinPorts also builds and (mostly) works under FreeBSD, OpenBSD, NetBSD, Solaris, and IRIX.
RLH 2005-10-31: I wonder if we could use something like this for the TPAN thing? It has a command line and a Tk gui as well.
New Tcl-based GUI to manage DarwinPorts packages: PortAuthority