Change Log:

Added Windows Explorer Context Menu management to Startup tool.
Added Windows 8 Release Preview compatibility.
Added Opera 12 support.
Updated History cleaning for Aurora.
Updated History cleaning for Chrome Canary.
Improved UAC bypass code.
Improved accuracy for uninstall items installation date and size.
Improved Scheduled Tasks detection.
Improved cleaning algorithm duplication detection.
Improved file and setting removal when uninstalling.
Minor bug fixes.

http://www.piriform.com/ccleaner/version-history
http://www.piriform.com/blog/2012/6/25/ccleaner-v320

Download
http://www.piriform.com/ccleaner/download

Download (Portable and Installer)
http://www.ccleaner.com/download/builds

Note: Be careful of any unwanted programs or toolbars that MAY BE prechecked.You do not need those for the program so uncheck them if you do not want them.