pmcyg can create customized collections of Cygwin(TM) packages. pmcyg takes a user-supplied list of Cygwin package names, and downloads only them and their dependencies from a Cygwin mirror, e.g. to create a CDROM or DVD based off-line installer.
I have always found it better to do a "cygwin download" first before doing the install to ensure that dureing the install network issues would not get in the way of cygwin install/update. I have also had the need to then copy the local install from directory to machines that have no direct access to the internet. This tool makes doing either of these tasks MUCH easire.
Thanks for Pmcyg, it's wonderful!