DeltaRPM is a tool that generates RPMs that contains the difference between an old and a new version of an RPM. This makes it possible to recreate the new RPM from the deltarpm and the old one. You don't have to have a copy of the old RPM, as it can also work with installed RPMs. The package also contains tools for creating and applying delta ISOs.
The Fink project wants to bring the full world of Unix Open Source software to Darwin and Mac OS X. It modifies Unix software so that it compiles and runs on Mac OS X and makes it available for download as a coherent distribution. Fink uses Debian tools like dpkg and apt-get to provide powerful binary package management. You can choose whether you want to download precompiled binary packages or build everything from source.
APT-RPM is a port of Debian's APT tools for RPM based distributions (Conectiva, Red Hat, SuSE, ALT-Linux, etc). APT is an advanced package management utility front-end which allows you to easily perform package installation, upgrading and removal. Dependencies are automatically handled, so if you try to install a package that needs others to be installed, it will download all needed packages and install them.
YOURI (Youri Offers an Upload & Repository Infrastructure) aims to build tools that make the management of a coherent set of packages easier. It assists in the many tasks involved with running a package distribution project, such as allowing individual maintainers to upload packages in a central repository, creating package indexes for package, synchronizing development resources such as CVS or bugzilla, advertising new packages, signing packages, and checking the consistency of individual packages or the global repository.