Looking for a POS expert I have a few questions.

I have started a business that specializes in POS security.  I was reading on some security blog that certian rootkit viruses can hide on POS terminals.  Is this true and if it is, how does Norton deal with this issue.  

I have learned (and this may be outdated) that rootkits are difficult to eradicate from large retail networks because the software to do it hasn't been fully developed. Is that still true? 

Does Norton have a "Stand Alone" program that just plugs in via USB that can run while the system is up and POS system is running?  It's difficult to sell this service as it is, without having to come in at a time when the owner/GM can reboot the system and boot off of the NBRT and the other programs I run.

Thanks for the help,

Jim