AVG Anti Rootkit Free is a free application designed for detecting and removing Rootkits on a system.
What is a rootkit some of you may ask? A Rootkit is a piece of software designed to conceal running processes, files or system data from the operating system. Virus and Malware creators often use rootkits to hide the existence of their viruses and malware and make them undetectable to tools like Virus Scanners and Process Viewers.

Screenshot:
AVG Anti Rootkit

Downloads:
Download from Official Site – 418.3kb