NBC Universal (NYSE: GE) says advertising inventory for the roughly 2,200 hours of online Olympics coverage next month is about 85 percent sold out, according to tells Mediaweek. Although many popular events—like swimming (Gold Medal finals), volleyball, boxing, track and field and gymnastics —won’t be streamed live, Zach Chapman, director, digital sales for NBC Sports and Olympics, is convinced that office workers will be glued to NBCOlympics.com, its dedicated site for showing the Beijing games, which begins on August 8th.

SEE ALSO: NBCU To Stream 2,200 Hours Of Olympics Coverage Live; Swimming, Gymnastics, T&F Not Included

Due to International Olympic Committee rules limiting the amount of marketing during the games, advertisers will run pre- and mid-roll video spots of 15 or 30 seconds— but no overlays. To make up for that, NBCU is working with marketers on customized spots. One example: a Hilton-sponsored video recap called “While You Were Sleeping,” which should help given the 12-hour time difference between the east coast and China. NBCU has also collaborated with Hilton on an online trip-planning section called “Destination Beijing” on NBCOlympics.com that uses the hotelier’s web-based booking tool.