BetterZip lets you quickly inspect archives without first extracting their contents.

Create and Update
• BetterZip can create archives with these formats: ZIP, TAR, TGZ, TBZ, TXZ, 7-ZIP, XAR, and — using the external commandline utility — RAR.
• Add files to or delete files from archives. Move and rename files inside archives.
• Compatibility: Have BetterZip remove Mac specific files from archives for archives that look and behave well on Windows.
• Edit archived files in an external application and BetterZip can update your archive.