Acer is the only company that is offering Android operating system in their all-in-one desktops. Meet the Acer TA272, a 27 inch all in one that doubles as computer display.
Specs of Acer TA272 include a 2560 x 1440 pixel touchscreen display, Nvidia Tegra 3 quad core processor, 16GB flash storage, 802.11n Wi-Fi, Ethernet, and Android 4.2 jelly bean operating system.
However, unlike your regular Android tablet, there is no battery inside, and with that huge size, you would not be putting it in your backpack too. You also get front facing stereo speakers (dolby audio) and 2 megapixel webcam.
Just like a normal computer, you can connect any peripheral via USB provided it is compatible with Android. Its display can be used using HDMI and Display ports.
Price, quite expensive, if you ask us. USD 999.