Short and Advent, Volume 2 by Valerie Floeter  contains miniature sacred solos, each about a minute long,  perfect for Advent worship services.  There are many occasions when a piece of less than a minute fits the requirement. Short and Advent, Volume 2 contains the following titles –

Come, Thou Long-Expected Jesus (RESTORATION)
Creator of the Stars of Night (CONDITOR ALME SIDERUM)
God’s Own Son Most Holy (GOTTES SOHN IST KOMMEN)
Jesus Came, the Heavens Adoring (SIEH, HIER BIN ICH)
Lift Up Your Heads, You Mighty Gates (TRURO)
O Bride of Christ, Rejoice (WO SOLL ICH FLIEHEN HIN)
O Lord, How Shall I Meet You (WIE SOLL ICH DICH EMPFANGEN)
O Savior, Rend the Heavens Wide (O HEILAND, REISS DIE HIMMEL AUF)
Prepare the Royal Highway (BEREDEN VÄG FÖR HERRAN)
The Angel Gabriel from Heaven Came (GABRIEL’S MESSAGE)
What Hope! An Eden Prophesied (CONSOLATION)
When All the World Was Cursed (WAS FRAG ICH NACH DER WELT)
When the King Shall Come Again (GAUDEAMUS PARITER)

Sample