St. Patrick's Day, Halloween, Mardi Gras. Those days that seem to, at least for college students, exist solely for the purpose of getting shit-faced drunk, with rituals often beginning as early as morning and continuing throughout the day.
Bob: Dude! I'm so drunk right now. We started drinking every time we see spongebob squarepants, and they are running a Halloween Marathon.
Ted: Happy Alcoholidays!
An occasion like Hallowe'en, April Fool's, or Father's/Mother's Day. Though not categorized as an official holiday, is often used as a good occasion to get a good drunk on with friends.
" Shit dude! It's Hallowe'en, my favorite alcoholiday! Let's get done up as Zombies and get druuuuunk!!!"