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In reading this thread I saw comments about BlackIce that I thought needed some warnings in return, but Waldo beat me to it. It’s good to know people here are already aware of Steve Gibson’s site. I get wary of “security experts” who don’t. 
For those who aren’t familiar with Steve Gibson, visit http://grc.com. It isn’t the easiest site to navigate on the 'net, but its tools will do the best job of testing your system’s security I’ve seen anywhere outside of hiring a consultant. And even the consultant may hit his site for a test.