Free: AVG Rescue CD
AVG has joined other AV providers by making available a free rescue CD. AVG Rescue CD is a portable version of AVG anti-virus built on top of a Linux distribution (Live-CD), Rescue CD is meant to help clean deep infections from systems that may no longer boot normally. Equally important is the included ability to update definitions over the Internet. 
AVG Rescue CD is a reactive tool, meaning it cannot prevent an infection from happening only remove them once they happen.
You can expect
- Comprehensive administration toolkit
- System recovery from virus and spyware infections
- Suitable for recovering MS Windows and Linux operating systems (FAT32 and NTFS file systems)
- Ability to perform a clean boot from CD or USB stick
- Free support and service for paid license holders of any AVG product
- FAQ and Free Forum self-help support for AVG Free users
Even if your current anti-virus says the infection was removed it could not hurt to run a second scan using AVG Rescue CD. No registration is needed to downloaded AVG Rescue CD. 
Links
avg, linux, live-cd, malware — Apr 1, 2010