How about this:
KACE "The Secure Browser uses virtualization technology to provide a safer web experience to users and organizations. When using the Secure Browser any changes or malicious files inadvertently downloaded from the Internet are contained within the secure browser, keeping the underlying OS and computer secure from hostile changes"
"Free/ runs on Windows 7, Windows Vista or Windows XP (32-bit only, 64-bit systems are not supported at this time)"
Provides a virtualized and contained Firefox v3.6 Browser with Adobe Reader and Flash plug-ins
Rapidly reset any changes made during normal use back to their initial state, enabling easy recovery from infections or attacks
View statistics related to the number of processes detected and blocked
Set white and black lists to limit access to known good sites, or prevent access to known bad sites to further limit the risk of attack and infection
Or, some other virtualization method to allow him to wack it and when he
logs gets off - so do all traces, but the goo on the keyboard(plastic or silicone covers for this or nurses could give and train in condom use).
Edit:
Download KACE direct!
Release notes