Open Source Software tools for IT professionals?

http://www.weethet.nl/english/hardware_bootfromusbstick.php
http://www.econsultant.com/i-want-open-source-software/index.html

check out “http://portableapps.com” it has a ton of USB bootable applications.
also wikipedia has a huge list, the like follows: “http://en.wikipedia.org/wiki/Portable_apps”

I also have heard of several anti-virus companies that offer free virus scanning from your web browser. This may be a possible option for you.

Good luck with your business