SPEC file generation

A .spec file is the 'recipe' by which the various pristine source, patches, and 'meta' information describing a package, its installation, upgrade, configuration and removal are formally described. It is used but rpmbuild (and formerly the deprecated rpm -b option series) to Build an installable binary representation for a given processor architecture and system library set.

perl-RPM2 - announced - by Chip Turner at Red Hat
Perl script to prepare .spec files out of CPAN perl modules - RPM::Specfile .
rpmrebuild - at Source Forge - by Eric Gerbier
Shell script to prepare .spec files out of a running installation's files by examining the RPM database, and building a .spec file.
cpan2rpm - at Source Forge - by Erick Calder
Perl script to prepare .spec files, RPM and SRPM out of an arbitrary perl module.