The Artifacts in the Library are, Tesla's Death Ray, The Holy Grail, Little Boy(Atomic bomb), The Ark of the Covenant, The Golden Fleece, King Midas, Excalibur, The Goose that laid the golden egg, Pandora's Box, Real Mona Lisa (Copy in Louvre), A Unicorn, Rocketeer's Jetpack, Ali Baba's Flying Carpet, and the Spear Longinus (Spear of Destiny).
When the elevator doors open and close at the bottom of the library, the sound made by the Turbolift doors from Star Trek is heard.
The Excalibur prop used in the movie bears the mark of collectible/film replica swordmaker Marto of Toledo, Spain, visible in close-up as Flynn draws Excalibur from the stone near the end of the film.