Creed's blog was a real website between 2007 and 2008. It is no longer active, but it can be found on Internet Archive.
Angela's "Goodbye, Kelly Kapoor" is improvised.
Steve Carell improvised the 'motorboating Jan's breasts' moment.
The background woman in a party dress who hails a cab during one of the Manhattan scenes was so distracting that the production crew had a hard time filming the scene as she kept missing her cabs. As she was not a hired extra, the production crew had her sign a release form.
Melora Hardin wore a custom-made, heavily padded bra and had shadow contouring to give the illusion of a breast augmentation.