Dixon Hill's business cards
A business card was a small piece of paper with a business or individual's contact information on it.
In 2000, Gerald Moss gave Shannon O'Donnel his Canton associate's business card. (VOY: "11:59")
In 2024, Q had Adam Soong's 3D printer printout his business card, which had his phone number on it. (PIC: "Fly Me to the Moon")
In 2364, while Jean-Luc Picard was playing the Dixon Hill holoprogram, Jessica Bradley took his (Hill's) business card. Later, after she had been murdered, Lieutenant Dan Bell used the card, which had been found in her purse, as evidence to bring Hill downtown for questioning. (TNG: "The Big Goodbye")