HP Slate 21 AIO is a 21-inch Android tablet, or is it a PC?

How big is a tablet before it becomes a computer? I only ask, because the new HP Slate 21 All-in-One is a humungous 21.5-inch Android tablet that thinks it's an all-in-one computer for your desktop.

Android software is usually found in tablets and phones and other things you can lift with one hand. But the Slate 21 takes it to the limit of tablet size, adding a kickstand to prop it on your desk. The Full HD screen isn't monitor-level resolution, but should be perfectly good for watching movies.

Inside, a super-powerful quad-core Tegra 4 processor and Android 4.2.2 Jelly Bean software ensure you're living life in the fast lane. After the thrill of having a giant tablet is gone, simply prop it up at a 30-degree angle on your desk with the kickstand, and plug in a keyboard and mouse for the peaceful easy feeling of a desktop PC.

If you ask me why anyone would make a tablet this big, I can't tell you why. But I can tell you why someone would make an Android PC: because for manufacturers, Android is cheaper software than Windows. And you know shoppers have already bought into Android, on their phones and tablets.

The HP Slate 21 AIO -- or Slate²¹, as some desperado at HP styles it --  goes on sale one of these nights: 1 October, to be exact, in the city and around the country for £370.

Samsung has also recently unveiled its own 21.5-incher on the border between desktop and tablet, the Samsung Ativ One 5 Style, which was unveiled alongside a tablet that switches between Windows 8 and Android, the Ativ Q.

Cameras that think they're phones. Phones that think they're tablets. Tablets that think they're laptops. And now tablets that think they're desktop computers -- or is it the other way round? I'm so confused, I want to curl up in a hole in the world away from all this.

Are Android PCs the new kid in town, or a recipe for heartache tonight? Tell me your thoughts in the comments, or take it easy on our Facebook page.