The Raspberry Pi is the only ARM PC, the only mini PC of this sort really, to became famous so far, but it might not have this monopoly for long.
There are noticeable differences between the Raspberry Pi and the Odroid-X, some of which might not be overly favorable towards the latter.
Odroid-X is about twice as wide, for example, and it is, naturally, a bit heavier, although weight doesn't really matter for such small things.
The other disadvantage of Odroid-X is the price. Raspberry Pi goes for around $35, or €28.66, give or take, but the newer gadget sells for $129 / €105.66.
Once onlookers finally take a close look at the hardware though, the reasons for all this become obvious: Odroid-X is, quite simply, better than Raspberry Pi.
One asset is the quad-core Samsung Exynos 4412 processor, with a clock speed of 1.4 GHz (Pi has a 700 MHz single-core). Another is the Mali 400 GPU (graphics processing unit).
Just as important is the amount of RAM. Where Raspberry Pi makes do with 256 MB, Odroid-X possesses one full Gigabyte.
As for connectivity, six USB 2.0 ports are present, along with an SD card reader, a micro HDMI output, an Ethernet jack and audio in and out.
Finally, Odroid-X can be bought with several addons, such as a Wi-Fi module, a webcam and an LCD panel (10 inches or 13 inches in diagonal).
Hardkernel, the company behind the product, allows orders to be placed on this page
. Both Android and Ubuntu 12.04 should run fine on it, leading to quite a bit of potential uses (Android Kiosk computer, HTPC, programming tool, etc.).
Of course, if you want to stick to the Raspberry Pi, there are various accessories for that thing too, like the Prototyping Pi Plate