You probably wondered about the Albert Einstein card, why is he playing poker with ST-CCG cards? These are what we call "Easter Eggs". A hidden object that wasn't there in the episode or a line in the lore that refers to thing the actor did. Most of them are for fun, some are as a tribute. You can look them up if you want to.

Here are the known Easter Eggs:

Premiere Edition
Albert Einstein He's holding ST-CCG cards in his hands.
Raise The Stakes There are ST-CCG cards on the table.
Red Alert! The number "23510" appears in corner of screen. 23510 is the ZIP Code of Decipher's office.
Alternate Universe
Berlingoff Rasmussen The actor who played Rasmussen, Matt Frewer, also played Max Headroom, Coke spokesman and short-lived TV series star. On Rasmussen's sweater, you can make out the letters M, A, and X, a reference to Frewer's previous role.
Interphasic Plasma Creatures It says [email protected] on the display. The old e-mail address for questions about rules.
Paul Rice Next to the copyright notice on the side of the card, "Paul is dead" is written backwards, a reference to many Beatles' albums that, when played backwards, supposedly said "Paul is dead". Ironically, the character Paul Rice was dead in the episode. The image on the card is a holographic re-creation of Paul.
Phaser Burns The person in this picture is wearing a patch on his arm showing the name "Dan Burns." Dan is Decipher's art director and the man responsible for the incredibly high quality of the images on the cards.
Rascals On the red sign it says: You must be this high to ride this ride.
Royale Casino: Blackjack The poker chip on the left bears the number "253," a reference to Decipher's 253 Granby Street address.
Senior Staff Meeting It says "[...] solutions to paramount problems" in the card's lore. The card's printed in1995, when Decipher had problems with Paramount.
Yellow Alert The number "07734" appears in corner of screen. If you look at that number upside down (especially on a calculator), it says "hello".
Aldebaran Serpent The translucent sphere forming the serpent's body reminded the art department of the Good Witch of the North from The Wizard of Oz, so they added the name "Glinda?" to the turbolift doors.
Canar It says "Franklin Mint" on the statue.
Data's Body It says CALL 911 on the transporter wall.
Data's Medals You can see the face of Gene Roddenberry in the glass.
Frigid The text "White X-Mas" is visible in Tasha's hair. A reference to the song "White Christmas" by Bing Crosby, Densise Crosby's grandfather.
Jealous Amanda Amanda's belt contains the words "POTION #9," a reference to the song "Love Potion Number 9" by the Clovers.
Mandarin Bailiff The red AIDS ribbon appears on the baliff's staff.
Mona Lisa There is a Federation shuttle right next to Mona.
Mr. Homn You can read the words "YOU RANG" on his jacket. A reference to the role of Lurch he played in the "Addams Family".
Q's Tent It says DECHIFFRER on the tent (Decipher in French).
Sonya Gomez The lore of the card says "Has total recall". The actress played in the movie "Total Recall".
System-wide Cascade Failure As an homage to noted science fiction author Isaac Asimov, the art department etched his last name into Lal's circuitry. Note the flipped "S," a subtle reference to the [S]ystem-wide cascade failure affecting Lal.
Timicin Dr. Timicin is played by actor David Ogden Stiers, who is well known for his role of Charles Emmerson Winchester III on the hit series M*A*S*H. Winchester was stationed at unit 4077, so they added these digits to the door frame behind Timicin.
First Contact
Reginald Barclay In the lore stands"Member of Alpha Team". A reference to the A-Team. Dwight Schultz played the role of H.M.Murdock in the populair TV-show.
The Dominion
10 and 01 The year in the copyright is printed in bynar.
Yelgren The Vorta has the "Music" skill because he's played by Iggy Pop.
Fajo Collection
Each card's copyright contains a letter, together and in the right order they spell "the art of great games".
1962 Roger Maris Baseball Card r
Black Hole e
Dixon Hill's Business Card g
DNA Metamorphosis t
Dr. Soong t
Guinan e
I.K.C. Chang a
Kivas Fajo e
Locutus of Borg r
Lore h
Miles O'Brien o
Persistence of Memory s
Picard's Artificial Heart f
Qapla'! t
Sisters of Duras m
Spot a
Tallera g
U.S.S. Pasteur a
The Trouble with Tribbles
B.G. Robinson It reads in the lore: "[...] Responsible for reporting the daily planet-to-ship transport logs". She's played by Teri Hatcher. She also plays the role of Lois Lane in the Adventures of Superman, Lois Lane is a reporter for "Daily Planet".
Dulmer Dulmer could also spell Mulder from the X-Files, that may be the reason why he has the skills  anthropology and exobiology. You can also read "Just wants the truth" in the lore.
Lucsly Lucsly could also spell Scully from the X-Files, which may be the reason he has the Medical skill.

Mirror Mirror
Ruk His lore reads: "Mysterious and spooky." A reference to his old role as the original Lurch from "Addams Family." Egg added by hatguy13.
Dr. Neria "Believes the truth is out there." The actor also played the character "Deep Throat"  from the X-Files.
Hull Breach Next to the copyright it reads:"THIS CARD SUCKS."
Kurros "Often does the exact opposite of what an adversary expects." The actor who played Kurros is Jason Alexander, also known as George Costanza from the TV-show Seinfeld. In one of the Seinfeld episodes he does the exact opposite of what the others expect.
The Pendari Champion It reads "THIS CARD ROCKS" next to the copyright. He was played by the known wrestler "The Rock", that's probably where he got his geology skill. "The Pendari Champion" is a reference to "The People's Champion" and "keen sense of smell" refers to the Rock's trademark "Do you smell what the Rock is cookin'?" "Electrifying" may refer to the fact that The Rock refers to himself as "The most electrifying man in sports entertainment today."

Holodeck Adventures
Leonardo da Vinci His lore reads:"dwarfed his contemporaries." A reference to the actors role as Gimli the dwarf in the Lord Of The Rings movies. Egg added by hatguy13.

Have you seen an Easter Egg not listed here? Please
mail me about it! I'll give you the credit for spotting it!
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