I don't see why you think Linux is any better at this. If you gave those same daughters a fully patched Windows XP box, turned on automatic updates, and gave them accounts that were only in the Users group (i.e. not administrators), their chance of getting infected would be zero, too.
There's plenty of malware that'll run just fine in userland as an unpivileged user, and plenty of other privliedge escallation attacks that can use the web.
Nothing has a "zero chance" of being infected .. including, apparently, machines that have never even been taken out of the box and plugged in (IBM shipping Aptivas with CIH preinstalled, for example...)
http://www.f-secure.com/v-descs/cih.shtml /mike. _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/