Duplicate Pokemon
Access a computer from any nearby Pokemon center. Save your progress and access the Deposit Box section of the PC, where stored Pokemon are held. Place the Pokemon you want to duplicate in any available space. Click the arrow on the left of the Deposit Box to change boxes. Select "Yes" when the game asks if you want to save changes. When the pop-up box displays "Saving, Don't Turn Off the Power," immediately turn off the Game Boy Color and turn it back on. You will now possess a duplicate of the Pokemon you sent to the deposit box.
Freeze The Game Clock
It's possible to freeze the game clock so that it permanently remains a certain day. Visit Vermilion City and start a conversation with the Machomp that is stomping the ground. After speaking with him, open your Pack and access the Coin Case. The game will either reset or freeze upon looking at the case. If the game freezes, simply restart "Pokemon Silver." The game will be frozen in the exact same time as your save file.
All Three Starter Pokemon
With this cheat you can obtain all three starter Pokemon instead of having to select one. Start a new game with an empty save file. After selecting a starter Pokemon work your way through the game and capture other Pokemon. Do not save your progress while doing this. Access the first Pokemon center and visit the PC. Deposit your starter Pokemon in the Deposit Box and complete the "Duplicate Pokemon" cheat from Section 1. When the game restarts, select the second starter Pokemon and repeat the process. Perform the "Duplicate Pokemon" cheat again, and then select the third and final starter Pokemon.
Simple Breeding
Breeding typically requires a male and female version of the same Pokemon. Instead, you can use a captured Ditto to serve as the female. Simply capture the male version of the Pokemon (like a Pikachu, for example) and have him breed with the Ditto to get the same results (a Pichu).