The Incredibles "First In Line" (partially found online trailers for Pixar animated film; 2004)
Prior to the release of Pixar's 2004 CGI-animated film The Incredibles, three online promotional trailers were made. They are titled First In Line, Still First in Line, and First in Line: SOLD OUT.
Information online about these shorts is sparse and primarily available through recollections of reviewers since the trailers are no longer accessible from the original Disney site.
According to one recounting, the trailers parodied typical Hollywood release hype. The first two shorts, First in Line and Still First in Line, are reportedly clips of a male fan of the upcoming film waiting in line.  The consensus online holds that these shorts weren't clips from the film; rather, they focused on advertising the premiere date.
These shorts were unexpectedly left off of the DVD and Blu-Ray releases for The Incredibles, much to the chagrin of many reviewers. Since being taken down from the Disney Geek website, the shorts have remained unavailable to the public.
On March 18th, 2020, the first advert was discovered on a promotional CD-ROM that was distributed in the UK. It has since been uploaded to YouTube.
While the shorts themselves are still lost as the remaining download links do not work, the filenames for the shorts were found:
Incredibles_TV2472_1stNLine_0750.mov (First in Line)
Incredibles_1stNLine_v2229_0056.wmv (Still First in Line)
Incredibles_1stNLine_SoldOut_1500.mov (First In Line "SOLD OUT")
Note that the file extensions may be different if references to this filename are found.