Lenovo IdeaCentre Horizon 27
This 27-inch all-in-one functions perfectly well as a desktop, but to see it really shine, push the spring-loaded hinge down and lay the system flat on your table, desk, or even the floor. There's even a collection of custom tabletop apps and games, including the requisite air hockey (seemingly the first app everyone thinks to play on a tabletop PC), Texas Hold 'Em poker, and Monopoly.
HP Envy Rove 20
The built-in kickstand is rock-solid and adjusts to different angles easily, and the Rove also features HP's standard Beats Audio subsystem, more USB ports, and a clever on-demand screen rotation button that keeps Windows 8 from flipping the image around every time you jostle the screen.
Sony Vaio Tap 20
The original Vaio Tap 20 came out last year and was one of our early favorites in the tabletop PC world. The landscape has expanded since then, and the new Tap 21 model (not yet reviewed) has an aluminum chassis and easy-fold rear stand/hinge that give the PC all the appeal of a well-build monitor/tablet with a bit of the feel of a TV. It's also 30 percent lighter than last year's model at about 8 pounds, despite gaining in inch in overall screen size.
Dell XPS 18
Thanks to its light weight and portability, the Dell XPS 18 is probably the most useful of the current crop of tabletop PCs, and it's fun for playing touch-friendly games. Rather than a built-in kickstand, it uses a heavy dock that stays anchored to the table (and that acts as a charging base), allowing you to pick up the tablet part and walk away easily.