Everyone needs a ZIP utility to open various compressed files, and up to now most of us have been using the almost free annoying WinZip. (sings Twisted sister: Were not gonna take it! Were not goooonnna take it any moreeeee YA!) Ok out there on the ol' source forge is a Zip archive utility that is completely free, much easier to use then WinZip with that annoying extra click through "No I don't want to purchase you AGAIN." Anyway this zip utility is called 7zip. It supports a "menagerie" of compressed files such as: ZIP, CAB, RAR, 7Z, ARJ, GZIP, BZIP2, Z, TAR, CPIO, RPM, DEB, R2D2 and C3PO. Ok not the last two but, for zip and gzip it provides a compression ratio that is 2-10% better than WinZip. Oh snap! And I know your head is spinning by now but their website claims that with the new ".7z" format it can compress to 30%-70% better than Zip format.
Get it here.