Portwell's WEBS-1010 might not look like much, but it's a functional PC that will fit in your pocket and play back HD content. And it's priced under $500.
Measuring just 4x4x1 inches, the fanless, XP-based system operates in complete silence. Storage is managed through MicroSD (though a 2.5-inch bay awaits modders), while a 1.6GHz Atom and 1GB of RAM power the system. And even with the small size, you get Wi-Fi (draft n), 6 USB ports (WTF), mini PCI-E, IR (for a remote) and HDMI-out. Portwell promises their system can output 1080P content, despite most Atoms falling a bit short in this department, through deployment of an Intel SCH US15W chipset (a combination of northbridge and southbridge tech).