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

Other days

unicorn

Unicorn Day
carpenters

Carpenters Day
ride the wind

Ride The Wind Day
cuddle up

Cuddle Up Day
aloxolt

Aloxolt Day
ruby

Ruby Day
one

One Day
gum

Gum Day
mean girls

Mean Girls Day
buddy

Buddy Day