(covers information from several alternate timelines)
Vulcan data chips from the 2150s
A data chip was a type of crystalline data storage device used by various species.
In 2152, Doctor Yuris gave Sub-Commander T'Pol a container full of Vulcan data chips containing all available research on Pa'nar Syndrome. (ENT: "Stigma")
Skagaran data chips from the 19th century
Later in 2153, on a Skagaran colony planet, T'Pol and Commander Charles Tucker III recovered some Skagaran data chips from a data module in a crashed 19th century Skagaran starship. After showing Captain Jonathan Archer the data chips, Tucker and T'Pol took the data chips back to Enterprise NX-01 in an effort to recover information on the history of the colony. (ENT: "North Star")
These data chips were not named on screen; their designation comes from the final draft scripts of "Stigma" [1] and "North Star".
Accessing a mirror universe Vulcan data chip
When the USS Discovery found itself in the mirror universe in 2257, Ash Tyler recovered a data core from the wreckage of a nearby Klingon raider containing what Michael Burnham recognized to be Vulcan data chips. These data chips were translucent blue, individually pyramid-shaped, connecting together in sets forming an octahedron. Burnham concluded from these data chips that, in that universe, the Vulcans were sharing technology with the Klingons through an alliance. (DIS: "Despite Yourself")
The props of the mirror Vulcan data chips appeared to be held together by four sets of magnets.
Soon after, the mirror Shukar provided Burnham the locations of rebel listening posts on a Vulcan data chip as part of a plan to deceive the Terran emperor. (DIS: "The Wolf Inside")
A Kerkhovian data chip
In 2259, the Kerkhovians left a data chip on the shuttle Cervantes after repairing the damaged caused when it collided with their transport tunnel. The chip contained routing instructions for contacting the Kerkhovians via subspace; it was thus characterized as a "calling card" by Ensign Nyota Uhura. (SNW: "Charades")
In 2401, Commander Ro Laren gave her Bajoran earring to Admiral Jean-Luc Picard just before her assassination. The earring was later found to contain a data chip detailing Ro's investigation into a widespread Changeling infiltration of Starfleet. (PIC: "Imposters")