Package Converter is an Alien front-end GUI that allows users to easily convert between file formats used in software packaging by some Linux operating systems such as deb (Debian), rpm (RED Hat), slp (Stampede), pkg (Solaris), and tgz (Slackware) with support of lsb packages. The application is written in Realbasic and Python and it supports all alien parameter options. You can find more information about Package Converter along with its author here.