On the Macside you could use this very useful little application called MacGZIP

>http://persephone.cps.unizar.es/~spd/gzip/




For TAR take a look at MacTar :
>http://www.strout.net/files/mactar.sit.hqx


Later,
T@W

(and there's ofcourse Stuffit, which IMHO has become too trashy)
KAPTON kills.
--