What is a good portable backup AV scanner to use?

I currently have Nod32 AV running but I would like to use another compact scanner to use as a backup incase Nod32 fails to detect something.

Basically, something like an online scanner but something I can keep on my PC for convenience. All I need from it are just manual scanning capability (I dont want real time protection), good definitions, reliable, and small in size and maintenance as possible. Free is another plus.

I am also interested in an Anti Trojan version as well.

Thanks.

 

Small portable AV's:
Free
Trend Micro Sysclean
McAfee Command line scanner
Fprot Command line scanner

Anti Trojan:
Free
McAfee Stinger

With all of the above they can be easily updated and as stated are free, also they do not need to be installed and can be run from a external media, I use these three in my Windows PE recovery disk. HTH

 

Microworld Free Toolkit Utility
http://www.mwti.net/
Basically a stand-alone Kaspersky scanner which require no installation.

F-Prot for DOS
http://www.f-prot.com/products/home_use/dos/
Works on Windows 9x systems.

Bitdefender Free
http://www.bitdefender.com/bd/site/downloads.php?menu_id=21

 

Based on the c't test, I'd say Bitdefender Free 7.2 is a decent choice, if you are willing to install a new (on-demand only) scanner that runs two processes on your system.