The disco ball from Studio 54 plays disco music and creates a vivid light show, particularly when it is smashed into the ground or lit up by a flare.
Possibly for entertainment. While it probably should have been packed tightly away in a box, where it couldn't have rolled to freedom, when it did make contact with the floor it played "I Will Survive" by Gloria Gaynor, ironically starting with the lyrics "It took all the strength I had not to fall apart" shortly after impact.
How it WorksEditAccording to Artie, this artifact operates by trapping "desires refracted by light, sound, sex...mind altering drugs into a disco ball." When activated, it "projects yearnings and cravings. It imparts a grim stampeding inhumanity against anything decent," so it basically makes you feel the same way the people who partied at Studio 54 did. Presumably, after hanging so long in the Studio 54 disco hall, the ball absorbed the energy of the place and, as a result, has been keeping disco "alive."
In an anthropomorphic sense, the disco ball represents one of the more "playful" artifacts and appears to simply enjoy having a good time. In the same sense, it appeared to be willing to help recapture Alice Liddell's spirit for storage. When it was lit up again by the laser Claudia had rigged, it started broadcasting the line "I've got all my love to give" from the aforementioned song. Also at the end of the episode the artifact seemed to show a sign of sentience when after the agents left, it sparked with a glow of energy and began to sing to itself again like it was in a good mood now that Alice was recaptured and it was hanging like it had been in Studio 54 where it was once housed.