Universal Extractor is a program do to exactly what it says: extract files from any type of archive, whether it's a simple zip file, an installation program, or even a Windows Installer (.msi) package.  This is still a work in progress (see details below), but so far it's proven quite useful and I feel others can also benefit from it.

Universal Extractor, like most of my Windows programs, is written in AutoIt, a powerful open source scripting language.  Universal Extractor itself, however, is just a front-end that uses many other programs to do the dirty work.