Mac only: iPackr is a free Mac app that, unlike many other unarchivers for OS X, gives you the option to preview and manually extract the files in an archive.
Our favourite file archive utility for Mac, The Unarchiver, is great because it integrates so well with the Finder. Just double click on an archive, and it'll extract it to that folder for you. If you're looking for something a bit more traditional and advanced, though, you usually have to shell out some money. iPacker lets you see what's in an archive before you extract it. You can add or remove files, convert it to a different archive type, or even live preview text and image files right from the app's built-in preview pane. It supports creating 7z, ZIP and RAR archives, and supports decompressing gz and bz2 archives in addition to the others.
iPacker is a free download for OS X. If you want support for password protection, you can grab its $1.99 cousin, iPack.