Symlink tree systems

encap
Stow
reflect implemented as a bash script, requires only bash, sed, and coreutils (or shellutils and fileutils in place of coreutils)
stowESa stow enhancement
Graft
srcpkg
Asis
Depot
Store
- Store
Softinst

Spkgtool a GUI package management system that can use its own builtin symlink tree system or act as a front end to graft, epkg, or stow.

RPM

Perl-RPM
RPM2 another perl interface
Yum an automatic package-installer and dependency-handler, similar to apt, but for RPMs

The Debian Package format

installwatch a program which logs the installation of packages from tarballs

CheckInstall a wrapper around installwatch that generates packages in either the deb, rpm, or slackware format

OSD a package distribution standard co-authored by Marimba and Microsoft

EPM a utility to create packages in multiple formats (DEB,RPM, various proprietary unix formats)