My favorite factoid that believers repeatedly assert is that Oswald was the only person missing from a mythical roll call.
This has been repeatedly refuted, yet believers simply wait a few weeks or a few months, then spout it again. We know beyond any reasonable doubt that the following people were missing at the time that it's claimed only Oswald was missing:
Jack Charles Cason - President of School Book Depositary - left the building at 12:10 p.m. and went home. (VOL:22

640)
Gloria Jean Holt - clerk at TSBD - did not return after shooting. (VOL:19

.526) (VOL:22

.652)
Sharon Simmons Nelson, Secretary, (VOL:19

.256;VOL: 22-P.665) did not return.
Bonnie Richey, Secretary, (VOL22

.671) did not return.
Carolyn Arnold (VOL:22

.635) did not return.
Mrs. Donald Baker, Clerk, did not return (VOL:22

.635)
Judy Marie Johnson (VOL22

.256) did not return.
Mrs. Stella Mae Jacob (VOL:22

.665) did not return.
Charles Givens did not come back.
Virginia H. Brnum - McGraw-Hill employee does not return (VOL:22

.636)
Vida Lee Whatley, Clerk, does not return.(VOL:22

.680)
Warren Caster (VOL;22

.641;VOL 26

.738) eating lunch in Denton.
Spauldin “Pud” Jones (VOL:22

.658) eating lunch at Blue Front with Herbert Junker (another McMillan employee) (22:659)
Mrs. Helen Palmer, clerk, (VOL:22

.666) not present was at Love Field.
Franklin Kaiser - was absent from work on 11/22.(VOL:6

.342), (VOL:23

.751)
Vicki Davis, employee, was absent.
Dottie Lovelady, employee, was absent.
Mrs. Rudell Parsons, employee, was absent.
Joe Bergen, Scott Foresman, absent.
Maury Brown, McGraw-Hill, absent.
John Langston, absent.