BetterZip Quick Look Generator lets you view the contents of compressed archives through OS X's Quick Look functions. Simply select an archive in the Finder, in Mail, or Spotlight and press the spacebar. You will immediately be presented with a neatly formatted table of the archive's contents that you can browse.
The currently supported archive formats are: ZIP, RAR, 7-Zip, TAR, GZip, BZip2, ARJ, LZH, ISO, CHM, CAB, CPIO, DEB, RPM, SIT, DiskDoubler, BinHex, and MacBinary.
You can change various view options, set whether hidden files in the archive should be displayed or not, and whether you wish to look into file packages.