Dunno if anyone's played with these much..but for the past several months I've begun to experiment with them. Many here have probably heard of these before..you take an old PC, stick in 2x NICs...and install one of the many different linux based firewalls..such as Smoothwall, m0n0wall, ClarkConnect, pfsense, IPCop, Endian, etc. The reason I'm bringing it up here..is because some of them are really getting into UTM (unified threat management)...features we're seeing appear on enterprise grade hardware that costs 3-5-10 thousand dollars and more. Besides the usual NAT...you have deep SPI, SNORT intrusion detection, application level transparent proxies for http/pop3/ftp/smtp...so they're scanned for viruses, spam, phishing, malware..at the gateway. You can also turn on adblocking for browsers, and robust content filtering. This can help with the ad/spyware. By default most of them run their AV with ClamAV..which updates itself..checking each hour. You can also get other plugins for other AV products if you favor them, such as F-Prot. I started with IPCop...on an older small form factor Compaq Deskpro EN..with a P3 833 with 256 megs. http://ipcop.org/ Pretty much a bare bones product, built on top of Smoothwall....easy install and config..basic features like most consumer grade NAT routers..plus VPN stuff. I then came across the plugin for IPCop..called "Copfilter. http://www.copfilter.org/ Here's where you can crank up the protection levels..adding all those transparent proxy features. And the computer I had started to feel the pinch of working harder. I also had a small form factor Compaq EVO d510 series small form factor..with a P4 2.4 and 512 megs. Same onboard Intel NIC, I took the hard drive out of the P3 box, along with the 3COM 905 I was using as a secondary NIC..put them in the d510...booted up just fine..ran much smoother. Then I came across "Endian". It seemed like a much more matured, groomed version of IPCop with the Copfilter add-on. It's built on top of IPCop actually...just..a more modern web admin, looks like a much more polished product. It's probably going to be a keeper for me. http://www.endian.it/ Anyways..just wanted to post these here..as in my opinion...they're great products..since they're bringing along some enterprise level UTM features. They bring added protection to your computer(s)/networks...since they do scanning at the application level as a transparent proxy...basically you're having added protection being done at your gateway...no performance hit to your rigs since you're not installing additional software on your PCs. They're free! Just take an unused computer...a barebones unit. You'll end up with a router appliance that will usually run circles around any home grade NAT router you bought at the store.