UnRarX is a free WinRAR-style tool for Mac which allows you to unzip RAR files.
UnRarX is very easy to use. Simply drag and drop RAR files onto the UnRarX interface and your files will be automatically unzipped. The extracting process appears in the main section of the UnRarX interface to indicate the progress of the extraction.
The main controls for UnRarX are in the top-right of the main interface. These functions allow you to browse for a file, extract files and test files to see whether they are corrupt. If your file is password protected, just press the 'password' button and enter it to open and extract the archive.
You may encounter a few problems depending on your file type. If you receive a CRC error, it's likely that one of your RAR archives is corrupted. Also, if you experience a "UnRarX cannot extract archive" error message, try re-directing the output volume to your desktop instead of File Directory. These little glitches can make UnRarX a bit tricky for beginners but most people should experience fre problems.
Unfortunately there seems to be very little developer support for UnRarX although there is a support page with links to a forum and bug report page, where you may be able to find help with problems you're having. Note as well that UnRarX only unarchives RAR files - it won't create them for you.
UnRarX is one of the closest things to WinRAR on Mac for unzipping RAR archives.