Often called: SnS
 What's Stop 'N' Swop?
Stop 'N' Swop is biggest mystery in Banjo-Kazooie, this mystery is even more famous than the Quagmire and Rusty Bucket Bay Door Link, the mysterious green door in Gruntilda's Lair, and Dream.
Stop 'N' Swop was planned for Banjo-Kazooie and Banjo-Tooie.
However, Rareware decided to make a plan to make Stop 'N' Swop work. But Nintendo turn down the plan because to make Stop 'N' Swop work because, it required Hot-swapping the game cartridges.
The reason why Nintendo turn down the idea is because they didn't want gamers to lose the game data.
Ever since Microsoft bought Rareware and had it's name change to Rare, Banjo-Kazooie and Banjo-Tooie are now available in the Xbox Live Arcade. With full Stop 'N' Swop capability.
 STOP 'N' SWOP: BANJO-KAZOOIE
At the end of Banjo-Kazooie, if all 100 Jiggies have been collected, Mumbo Jumbo will show the player three animated photographs which reveal the locations of two Mystery Eggs and the Ice Key, in locations that players may have noticed previously to be inaccessable. However, after waiting until Banjo-Tooie's release, fans felt like the solution offered in Tooie was a copout. Members of The Rare Witch Project set to work hacking the game, and made a shocking discovery. There are in fact codes within the game that can be entered on the Sandcastle floor in Treasure Trove Cove that will allow anyone to reach these treasures, as well as another four eggs not mentioned by Mumbo. Once the items are collected, a menu appears on the pause menu if you move to the very end past Click Clock Wood. It has never since been discovered what this menu is for, and indeed what it does.
Cyan Mystery Egg
The Cyan Mystery Egg is found in the cellar of Mad Monster Mansion, in a barrel marked "1881" that has been crossed out.
The code: "CHEAT DONT YOU GO AND TELL HER ABOUT THE SECRET IN HER CELLAR"
Pink Mystery Egg
The code: "CHEAT OUT OF THE SEA IT RISES TO REVEAL MORE SECRET PRIZES"
Blue Mystery Egg
The Blue Mystery Egg is found in Gobi's Valley, behind an unopenable door which Gobi sits by before leaving the desert. The egg can be found inside a sarcophagus in the proceeding room. (Mumbo reveals it after getting 100 Jiggies)
The code: "CHEAT A DESERT DOOR OPENS WIDE ANCIENT SECRETS WAIT INSIDE" opens the tomb door
Green Mystery Egg
The Green Mystery Egg is the second egg to be found in Mad Monster Mansion, on top of Loggo
The code: "CHEAT AMIDST THE HAUNTED GLOOM A SECRET IN THE BATHROOM"
Red Mystery Egg
The Red Mystery Egg is found in the captain's quarters in Rusty Bucket Bay, accessed via breaking one of the windows.
The code: "CHEAT THIS SECRET YOULL BE GRABBIN IN THE CAPTAINS CABIN"
Yellow Mystery Egg
The code: "CHEAT NOW BANJO WILL BE ABLE TO SEE IT ON NABNUTS TABLE"
The Ice Key is perhaps the most mysterious Stop 'N' Swop item, predominantly because it is the only item that can be seen during normal play. It is found in Wozza's cave, in a small alcove; if the player uses first person mode, they can see through the ice to see the key twirling, but there is no way to get in. However, typing in the following code removes the unbreakable ice wall. (Mumbo shows you it after getting 100 Jiggies)
The code: "CHEAT NOW YOU CAN SEE A NICE ICE KEY WHICH YOU CAN HAVE FOR FREE"
 STOP 'N' SWOP: BANJO-TOOIE
In Banjo-Tooie, the Ice Key could be found in a cave around the sandy area of Jinjo Village. It unlocks a large Ice Vault that holds the Mega-Glowbo. The Mega-Glowbo can be used in Humba Wumba's wigwam at the entrance of Witchyworld to transform Kazooie into Dragon Kazooie.
Pink Mystery Egg
Blue Mystery Egg
It's behind the waterfall in Spiral Mountain.
Yellow Mystery Egg
Found in Heggy's House, however must be hatched by Kazooie.
 STOP 'N' SWOP: BANJO-KAZOOIE & BANJO-TOOIE XBLA
Unlike the original Banjo-Tooie the Stop 'N' Swop items are not available in the game unless they were collected in Banjo-Kazooie (XBLA) in which case the player starts with the items already collected. (The SnS items will be available in Banjo-Kazooie once you have a save file in Banjo-Tooie or Banjo-Kazooie: Nuts and Bolts. This includes the Nuts and Bolts Demo.) Heggy will hatch all the eggs which will unlock the three awards from the original (Breegull Bash, Jinjo as a multiplayer character and Homing Eggs) along with a gamer pic, a Xbox theme and Stop 'N' Swop II. The Ice Key is still used to access the Mega-Glowbo.
 STOP 'N' SWOP: REFERENCES
- In Grabbed by the Ghoulies, there is a chalkboard that reads "Collect Ice Key. Collect 4 eggs. Open Secret Level." This has been presumed no more than a way to mock fans, but it is unknown whether it's fake.
- It should be noted that, although only 3 mystery eggs and the ice key were used in Tooie, the Stop 'N' Swop fanfare is played when collecting all 6 eggs along with the key. This could suggest that all 6 eggs were originally planned for use as part of the process.
- Stop 'N' Swop has been mentioned various times in Banjo-Kazooie: Nuts & Bolts. Bottles pretends to offer the secret of Stop 'N' Swop for 6000 notes (despite the fact that there aren't 6000 notes in the game), but steals your notes and says "I would tell you, but I have to kill you, and we don't want that in an E-rated game.". A few mystery eggs and a fake ice key are in Banjoland. Paintings of the eggs and an imprint of the Ice Key around Showdown Town and Boggy's Gym. These will give parts when the eggs are collected in Banjo-Kazooie on the XBOX Live Arcade. (Beacon, Goldfish, Mole-on-a-Pole, Googly Eyes, Fluffy Dice, Flag (2x), & Disco Ball)
- There is an ice key in Banjo's dumpster in Spiral Mountain. (along with Fergy the Fudgehog from Viva Pinata, and some Grabbed by the Ghoulies baddies.
- In Banjo-Pilot If you Cheato some Cheato Pages for information about Stop 'N' Swop, he will just say "Why won't you just swop this game for a nice book?".