Nokia prototype tablet (images)
These images, posted in the Windows Phone Central Forums by Rubik_H2CO3, may or may not be legit. The specs are a bit dated: Tegra 3 1.3Ghz processor, 2GB RAM, HDMI-OUT, USB Port, SIM Slot, 16point touchscreen, running Windows RT. The poster notes that they think this prototype was dropped due to the Tegra 3 chipset, which is used in a handful of Windows machines these days.
Second picture looks a lot like a Surface.