The Acer Aspire Revo RL70 seems to have been designed with a view to fit in as small a space as possible. This Nettop only takes a 1L volume, thanks partly to a gem-cut design, and is available from Ebuyer for £200 with free delivery.
It runs on an AMD E450 dual-core APU clocked at 1.65GHz with a Radeon HD6310 onboard GPU and Windows 7 Home Premium. Note that Acer also offers a free upgrade to Windows 8 Pro which is applicable to this SKU. Just download the OS from 26 October and install it on the PC for £14.99, then fill in a form on Acer’s dedicated Windows 8 Upgrade website and get a £14.99 refund.
Other features include 3GB of RAM, a 320GB Hard drive spinning at 5400RPM, Dolby Theater audio enhancement, a USB keyboard and mouse, GbE, Wi-Fi, six USB 2.0 ports, D-Sub, SPDIF, a card reader, two PCI Express mini card slots, HDMI, a stand that doubles up as a TV bracket and, surprisingly at this price, even a DVD writer.
If you don’t want or don’t need Windows, then you can grab the same Nettop with Linux for £10 less and a model with 4GB of RAM and 640GB hard drive for £195.50, both from Ebuyer.