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

Other days

lisp

Lisp Day
self appreciation

Self Appreciation Day
buddy

Buddy Day
bow tie

Bow Tie Day
camera

Camera Day
law

Law Day
blanket fort

Blanket Fort Day
martini

Martini Day
boyfriend

Boyfriend Day
hiv awareness

Hiv Awareness Day