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

Other days

ruby

Ruby Day
book

Book Day
lash

Lash Day
buddy

Buddy Day
believe

Believe Day
bubble bath

Bubble Bath Day
my little pony

My Little Pony Day
lisp

Lisp Day
tell a fairytale

Tell A Fairytale Day
unicorn

Unicorn Day