The Big U says, quoting the Howie interlude from Backstreet Boys' "I Want It That Way":

"You are (you are, you are, you are)."

The Big U is from Wid's Daily, 1919.

Here's the word "semiantireprophetical" in the wild.  From "The Great Hug" by Donald Barthelme, in Folio, Jan, 1976.

Not only do we like the headline, but this article about an "E" quotes a "Mrs. X."  From The Martlet, 1963.  See One-Letter Words: A Dictionary.

"God made not anything at all so beautiful as words." —Anna Hempstead Branch. 

From Taylor's 1963 yearbook.

Learning perhaps ought to quit sleeping and snoring so as to grasp how to properly pluralize "library."  From National-Louis' 1969 yearbook.

"In the wilds of fiery climes he made himself a home, and his soul drank their sunbeams."  From Manual and Diagrams to Accompany Metcalf's Grammars, 1901.

"I wish something that rhymes with boat would strike me."  From Otterbein's 1911 yearbook.

We use measuring tape as a bookmark so that we're always ready for big words.  From The Film Daily, 1937.  See Webster's Dictionary of Improbable Words: All-Consonant and All-Vowel Words.

We, too, use three straws when we h-ss-c-c-s-l-r-r-p.  For more all-consonant words (essential for word gamers!) see Webster's Dictionary of Improbable Words: All-Consonant and All-Vowel Words.

From Colorado College's 1940 yearbook.

That "living on velvet" is now an antiquated expression leaves us "crushed."  From Film Daily, 1935.

It's "s'more" or "finis," depending on how you look at it.  From Swarthmore's 1895 yearbook.

"L is not a letter I care very much for," says Prof. Stokes in Dark Shadows.  See what you think of L's many meanings, in One-Letter Words: A Dictionary.

The Scarlet Letter is defined in One-Letter Words: A Dictionary.  From The Film Daily, 1926.

For spellworkers only: a sorceress we know from the fire ceremonies at the Goddess Temple in the Nevada desert, Abigail Spinner McBride, has premiered our Kabbalistic magic spell against the coronavirus.  The video clip is 3 minutes long, and the link to Youtube should begin at 32:16: video.

A “glompf” sort of day appears in “Epitaph For a Tombstone Day” by Loraine DiPietro, in Ethos, 1963.

The Big U says, quoting Kina's "Get You the Moon":

Note that the Big U may have misheard the lyrics as three one-letter words: "O, U, R."

The Big U is from Wid's Daily, 1919.

"You will greatly oblige me by sending those books."  From Manual and Diagrams to Accompany Metcalf's Grammars, 1901.

We, too, have been to collage and are therefore less easily fooled (though, admittedly, we find ourselves stuck to various materials).  From Wake Forest's 1969 yearbook.

The word "gleebus" is very rare, with fewer than 90 Google results.  As shown here, a gleebus is the creature that eats telephone receivers.  From UNC Chapel Hill's 1963 yearbook.

If we're to trust Google Maps, this place is either "Desert Oraoracle" or "Desersert Oracle," depending upon how you approach.  Note that there are two mail slots on the door, presumably one for each parallel universe.  Here's the link, not that you wouldn't believe us.  [Update: they saw my post and fixed the glitch!]