Nick appears as a graphic designer in the episode, Job Fair. Pam approaches him and writes an application for graphic design which leads her to go to Art School.
Nick quits Dunder Mifflin-Sabre and helps inner city kids with computers. Dwight tells Nick that inner city kids use computers for two things: games and porn. His last appearance is the last episode of season 6, Whistleblower.
In WUPHF.com, he is indirectly mentioned as Glasses.