Zipeg - 1.62MB (Open Source)
Zipeg is a file compression tool, which offers the convenience of previewing an entire file before extracting it. It supports popular archiving formats such as ZIP, RAR, 7Z, TAR, TGZ, BZIP2, ISO, CBR, CBZ and many others.
With Zipeg you can open a compressed file, sort file-names in alphabetical order, view its content and extract the content from it. It also supports auto-detect file-name encoding and you can preview images, not just various documents. Zipeg supports content extraction from password protected archives that are encrypted, such as ZIP and RAR files including those that contains multiple parts. There is an Options button that allows you to select the file you would like the application to open by default, and also where you would like the destination file to be placed.
Zipeg is a great tool for previewing compressed files. For its functionality, it really is quite lightweight and uses hardly any system resources. It has a clean interface that can be navigated by users of all levels of experience, as there is virtually zero learning curve; simply install and use. The only downside is that Zipeg is unable to create archives, but then again, it doesn't claim to.
Note, Zipeg requires Java to operate.