Back in 1998 Rareware LTD. made a game perfect in all respects, this game is known as Banjo-Kazooie, gamers loved every aspect of this game, myself included, but one mystery remained. Rare had hinted about something known as Stop'N'Swop, if one found all the items in the game (excepting the S'N'S items) Mumbo Jumbo would show you a cutscene showing Banjo and Kazooie finding three of the seven S'N'S items, the three most commonly featured items, a large pink mystery egg, a large blue mystery egg, and an Ice Key. These items caused much hype and were a major cliffhanger for the upcoming game Banjo-Tooie, as Mumbo Jumbo said they would come in handy in the new game. However, gamers were dissapointed as they were led to believe it would be much better than it was, so enter IceMario and SubDrag, these two men (?) working together for the good of mankind (okay maybe that stretches the truth a bit but hey, it works.) They found gameshark codes to unlock six eggs and of course, the fabled ice key. Later, they found in-game codes that produce the same effect, but require no external sources to work (gameshark, emulator, Etc.) While these are by no means my discovery, I only wish to enlighten those who have not heard of them, or wish to learn from a trusted site.

Step 1: The Mystery Pink Egg

The pink egg is perhaps the most famous egg of them all, as it is the only one to actually alter a level to make a home for itself, it is also featured in a painting in Banjo-Tooie behind Blackeye The Pirate.
To find the egg, go to Treasure Trove Cove, go into the sandcastle (To the right of the entrance of the level and drain the water by talking to Leaky. Beat Grunty's word challenge if you have not already, then leave the sandcastle and go back in, after you do this enter the word CHEAT in the letters on the floor, you will hear a MOO sound after each letter, then enter the sequence OUTOFTHESEAITRISESTOREVEALMORESECRETPRIZES, you will then be treated to a cutscene of the risen sharkfood island. Enter the risen sharkfood island through the hole in its side (watch out for snacker) you will hear a sort of fanfare when you enter, this will play every time you enter sharkfood island, then use the shock jump pad (useless if you haven't learned it from bottles yet, which makes no sense as you learn it in treasure trove cove) then you will bounce up and land in a little alcove in the rock, there are 16 of these going in a spiral up the column in the center, you will need to flutter-jump from one to the other until you reach the top (this is by far the trickiest item to obtain) then pick it up Kazooie will remark on the egg, and it will be added to a new menu in your totals known as Stop'N'Swop thus giving it its title which would stick to this very day.

Step 2: The Mystery Blue Egg

This egg is the second egg featured by Mumbo Jumbo in the end scene, it is very famous as it lay dormant behind an unopenable door in Gobi's Valley, this door drove gamers crazy as they knew something important was behind it, but no matter what was done to it, it remained firm, never opening, until Icemario and Subdrag found a way.
To find this egg, as before go to the sandcastle, kill the Armored Snippet, and enter the sequence (beginning with the word cheat which for some reason, moos,) ADESERTDOOROPENSWIDEANCIENTSECRETSWAITINSIDE. While not complicated, many were stumped to find nothing in the room but an old sarcophagus, in front of it however, is a hexagonal golden pad, pound this and the sarcophagus opens, collect the blue egg inside as before (there are no traps, although this level is notorious for them.)

Step 3: Mystery Green Egg

The green egg, while not as well known as its Pink and Blue counterparts, is nevertheless famous for being the only egg paired with another in the same level (Mad Monster Mansion.) The gamers are unsure whether or not the egg was originally colored green, or it is green because it was in a bathroom for an unspecified period of time (mine was in the bathroom for nine years before I found it.)
To find this egg, return to the sandcastle as before, enter CHEAT, enjoy the mooing noises, and then enter the sequence AMIDSTTHEHAUNTEDGLOOMASECRETINTHEBATHROOM. You will be shown a cutscene of the green egg on a toilet, (For some reason named loggo.) Entering the bathroom on the second floor of the mansion (found after breaking a lighted window) you will hear the fanfare and music, then you may jump to the top of the toilet, (you only get flushed down after being transformed into a pumpkin so don't worry) then you can collect the egg, and return to the sandcastle again.

Step 4: Mystery Cyan Egg

The cyan egg is the brother of the green egg, they both exist in the same level (the only level to feature 2 items instead of 1 or 0) the egg exists in a large barrel that is stored in a wine cellar, the barrel is labeled 1881 (giving you an idea of how old this mansion really is) which is supposedly full of Wine, all of the other kegs are openable and contain innocent things such as jinjos, feathers, extra lives and the like, but this one remained stubbornly unopenable, leaving gamers to wonder "what the heck is in there?"
To find the blue egg, enter the word cheat (it will always moo) and then enter the sequence DONTYOUGOANDTELLHERABOUTTHESECRETINHERCELLAR. you will see a scene of the egg on a pedastal of sorts, go to the cellar of Mad Monster Mansion and the barrels cap will be gone, go into this barrel and walk through a shortish tunnel, you will end up in a puddle of water (or something like that) and you can splash through that to get the egg. Congratulations you are more than halfway done.

Step 5: Red Secret Egg

While this egg is in the hardest level, it is the easiest to obtain, it is also among the more mysterious items, as it is in the cabin rumored to belong to Captain Blackeye, Gamers are not sure of this however, but it seems only fitting that Blackeye, should be captain of Grunty's ship, and it seems only fitting that this cabin is the captains as it is the biggest and most decorated (except for the pipe slug, I don't know what he is doing there.)
To access this item, enter CHEAT (yes it still moos) into the sandcastle, followed by the sequence THISSECRETYOULLBEGRABBININTHECAPTAINSCABIN. You will see a cutscene of the egg on the bed, then you can go to rusty bucket bay and begin smashing portholes on the side of the ship with the rat-a-tat-tap (did not make up that name Rare did) and soon you will find the captain's cabin, fairly straightforward, then you can go back to the sandcastle for the next code, but you've got a long trek after that.

Step 6: Yellow Secret Egg

While this egg is pretty and completes the half dozen eggs you must get, it is also one of the most heavily guarded, you must climb up a tree thousands of feet high (hyperbole I know) and laden wih enemies and traps, to get to Nabnut's house, which is about halfway up the tree, and if you get hurt, there is a very high probability you will fall off, and an even higher probability you will die (or at least be very badly hurt) unless you have the double honeycomb puzzle completed, and after that you have to climb all the way back up. that is why i recommend using the flying pad, as it is only available during winter (which is when you go to get the egg from Nabnut's house).
To access the final egg and the near completion of Stop'N'Swop you must go to the sandcastle (for almost the last time) enter CHEAT (moo) followed by the sequence NOWBANJOWILLBEABLETOSEEITONNABNUTSTABLE, again the cutscene of the egg on Nabnut's table, go and grab the egg, and return to the sandcastle for the last time.

Step 7: Ice Key

The final item, the ice key, it is of unknown or forgotten function, and the lock to which it belongs may have long since melted, but the key lives on, it is unknown how it stays frozen in that backpack of banjo's, or how he even fits it in there in the first place, but one thing is certain, you'll be glad to finally get it. If you are observant, you may have seen the ice key behind the unbreakable wall in wozza's cave (near the orange jinjo and the 2 gold feathers) you can watch it spin around, hovering eerily, but today is the day you will finally obtain it.
To obtain the final item and complete the lucky 7, you must go to the sandcastle and enter CHEAT (MOO!) then enter NOWYOUCANSEEANICEICEKEYWHICHYOUCANHAVEFORFREE and you will see (for the final time so enjoy it) a cutscene of the key, freed at last, so run to wozza's cave. and get the key, then bask in the glory of the completed Stop'N'Swop.