Oops, it doesn't look like 'spiral ham day' is a national day..

Other days

artists

Artists Day
bonang

Bonang Day
bubble bath

Bubble Bath Day
stud

Stud Day
lumpy rug

Lumpy Rug Day
gum

Gum Day
lisp

Lisp Day
latina equal pay

Latina Equal Pay Day
cat girl

Cat Girl Day
kiss a ginger

Kiss A Ginger Day