A hardware based firewall I think is better than a software one. But the software one is an additional layer if you want it. I don't run Sygate routinely but then I don't have to. My computer is pretty much invisible outside my firewall. I am sure there are ways to hack into it but I have taken reasonable steps in any event to secure it.
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">By and large our protection is large numbers and little in our computers that anyone else wants.</font>
I don't quite see it that way. Script kiddies can use software that scans thousands of computers and finds the vulnerable ones, not to mention more sophisticated worms that people build using toolkits provided by a few brilliant trouble makers.
Together, this means we are all vulnerable to computer attack. There is a little so-called "security in obscurity" but not much.