AVADirect should include a bumper sticker with its Clevo P180HM notebook that says, "My desktop replacement beat up your Ultrabook and defiled your MacBook Air." Don't get transfixed on the notion that someone would be silly enough to own both of those ultraslim systems rather than choose one over the other. The point we're trying to make is that the P180HM is big, it's mean, and it makes a complete mockery of the mobile form factor. And you know what? We're totally cool with that.Let's talk a moment about portability versus mobility. These aren't one in the same, and if that has you scratching your head, follow along, it will make sense in a moment. A Zenbook is mobile. So is your typical 15.6-inch notebook, and even some 17-inch systems. But there's a line in the sand between notebooks and desktop replacements, and once you cross it, your system is no longer mobile, it's portable.The P180HM weighs upwards of 12 pounds, which is too heavy to toss into your bag on a whim or open up in a coffee shop and blend in inconspicuously with the other patrons. No, you carefully close up the P180HM, lift with two hands, and pack it neatly into your oversized laptop bag that's big enough to accommodate an 18.4-inch notebook. When you take it out at Starbucks, you mark off your area with yellow tape, tell everyone to stand back, and then place it on the coffee table with a thud. Your latte sits on the floor next to your foot, because there isn't room for it on the table, and because the P180HM would probably guzzle it up anyway. And you better be sure you're near a power source, there's no such thing as all-day computing on a desktop replacement.The trade off you're making with systems like the P180HM is far less mobility for a whole heck of a lot more power in a form factor that's still portable. To wit, the customizable P180HM we received rocks a fast Core i7-2760QM quad-core processor, a heaping pile of RAM (12GB), and not one, but two GeForce GTX 560M GPUs configured in SLI. It's built for gaming on the go, and with an 18.4-inch LED backlit display, it's big enough to at least consider using as your main system at home. In fact, the P180HM is better spec'd than most mainstream desktops, and even rivals higher end machines. But unlike your desktop tower, you can have the P180HM packed up and ready to head out and kick some tail at the LAN party across town in under a minute. That's what we mean when we say it's portable. But is it practical to drop over two and a half large on a notebook of this caliber? Let's tackle that question beginning right now.