The Heirloom Toolchest is a collection of standard Unix utilities.
Highlights are:

  * Derived from original Unix material released as open source by Caldera
  * Up to four versions of each utility corresponding to SVID3/SVR4,
    SVID4/SVR4.2MP, POSIX.2/SUSV2, and 4BSD (SVR4 /usr/ucb)
  * Support for lines of arbitrary length and in many cases binary input data
  * Support for multibyte character sets, especially UTF-8
  * More than 100 individual utilities including bc, cpio, diff, ed, file,
    find, grep, man, nawk, oawk, pax, ps, sed, sort, spell, and tar
  * The cpio utility can read and write zip files, GNU tar files, and
    the cpio formats of Cray UNICOS, SGI IRIX (-K), SCO UnixWare (-c)
    and Tru64 UNIX (-e). It is also available with the pax interface
  * Extensive documentation including a manual page for any utility
  * Runs on Linux, Solaris, Open UNIX, and FreeBSD

WWW: http://heirloom.sourceforge.net/