For the Season Nine DVD release of "The Office", they put together some old audition tapes of famous TV actors who DIDN'T get cast in the show. 

Back then, some of them were still unknown. 

They actually had Seth Rogen try out for the role of Dwight.  Bob Odenkirk read for the part of Michael Scott, and Eric Stonestreet from "Modern Family" auditioned as Kevin. 

John Cho from "Harold and Kumar Go To White Castle" and Adam Scott from "Parks and Recreation" both read for the part of Jim.

Check it out: