The original UK series ran on Channel 4 and was the creation of Graham Linehan, who's also responsible for "Father Ted" and "Black Books."
The British series was a winningly geeky sitcom about the IT department at Reynholm Industries, an upscale company with an incomprehensible business model, and included gags about the Armin Meiwes German cannibalism incident and a website created to help the hopelessly sports ignorant fake knowledgable conversations about last night's game. It was very funny, and among others starred Richard Ayoade and Chris O'Dowd, whose stars have since been on a rise in the world of film (Ayoade, in addition to acting, directed last year's "Submarine").
The US version, which you can watch below, has Ayoade back in the part of Moss and the not nearly nerdy enough Joel McHale taking on the role of Roy, originated by O'Dowd. This pilot was filmed back in 2007 and was actually greenlit by NBC until being killed off by new chairman Ben Silverman. The episode below doesn't work nearly as well as the UK version, but is an interesting look at what might have been -- McHale, of course, ended up in "Community" not long after, while Ayoade will next be seen in the Ben Stiller comedy "The Watch."