Who built the Arc? Sony, apparently - the company has just been revealed as the owner of PlayStationArc.com.
VGChartz made the discovery, and found that Sony acquired the domain on 6th October 2009. Dun dun dun.
However, Sony does not own www.ps3arc.com - a website depicting the PS3 wand, autumn release date and promise of a "Kownage Expansion Pack", which sounds suspicious.
Arc is of course the rumoured name of Sony's motion-sensing PS3 wand, which was delayed recently from a spring 2010 release and moved to an autumn launch.
With GDC in March and E3 this summer, there are two golden opportunities for a big-splash name reveal. Whether Microsoft has had the same idea for codename Natal, we'll have to wait and see.