Copy items, over level 100 pokemon, and a strange creature
From Glitches
From the games Pokemon Red/Blue and Pokemon Yellow for the Game Boy
Put the item you want copied into your sixth item slot. Now, fly to Viridian city and talk to the old man who teaches you about pokemon (he is in the upper left of the village). Say no to him so he will show the pokemon-catching demo. Then, fly to Fuschia City. Surf down and to the left (past the swimmers) and you will come across an island. If you surf up and down its edge, you will eventually find a pokemon called missingno or m. Whatever you do, just kill it. If you catch it, strange things may happen to your game (your elite 4 status may get screwed up). After you fight missingno, the item in the sixth slot will have over one hundred items, indicated by weird symbols as its quantity.
Instead of surfing on the island by Fuschia, you can also surf on the right coast of Cinnabar Island, on the area where the land meets the water. Either place, you may find pokemon that are at or above level 100. If they gain experience, they will revert back to level 100. You can also trade them without injury. It is thought that the possible level 100 pokemon and the name of the glitched pokemon may depend on the name of your charater. Beware of this glitch, however - it PERMANENTLY messes up your Pokemon hall of fame. Also, if you catch a pokemon similar to missingno labelled "-M-" and send it to the computer, your game will freeze when removing it.
Submitted by: Glitched Symbols and NeotheChickenGod
A Youtube video of this glitch can be seen here.
