Smaller than a CD drive and selling for $440, the Linutop 2 is powered by a 500-MHz AMD Geode LX800 processor. The system comes with 512MB of system memory and 1GB of flash memory storage, of which 400MB is available for use. Without a fan, it is eerily quiet to use, but the system keeps its cool. Minimalist in the extreme, the Linutop 2 doesn't come with Wi-Fi, Bluetooth or an optical drive. There's room to add a 2.5-in. hard drive inside, but the only item that's really meant to be upgraded is system memory; it can hold up to 1GB. The whole thing weighs just 1.25 pounds, allowing you to do something that few other PCs can: Velcro it to the back of a LCD monitor or, with Linutop's $55 adapter, screw it in place.