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

Other days

gum

Gum Day
pick me

Pick Me Day
slime

Slime Day
bow tie

Bow Tie Day
ruby

Ruby Day
brow

Brow Day
embarrass your best friend

Embarrass Your Best Friend Day
pampering

Pampering Day
prosecco

Prosecco Day
get funky

Get Funky Day