Gold/Silver Cheats
POKEMON/ITEM DUPLICATION
This cheat is really risky, but real useful for all you cheaters out there. It's a code that duplicates a Pokemon, and the item attached to it, if any.
Save your game right in front of a PC. Deposit the Pokemon to be duplicated. Go to the change box screen and change to another box. When it asks you to save, say yes. When the SAVING, DO NOT TURN OFF THE POWER message comes up, when POWER shows up, shut off your game. Now turn it back on. If the cheat worked, there would be a copy of the Pokemon you deposited back in your party, and another in the PC. This is because the Bill's PC data is saved before your own party member data. Don't withdraw any Pokemon right before this code (e.g. after the first, real save, and before the duplication "save") or you'll lose it.
Remember, this code is highly risky, so try it only if you don't mind losing whatever Pokemon you're trying to duplicate. This was also in the Japanese version, and I guess Nintendo of America overlooked it. I know of some people who lost valuable Pokemon because they shut off the game at the wrong time, so just remember that I've warned you.
TIME CHANGE
Next, there's also the Time change code. Press Select+Down+B at the screen where Ho-Oh or Lugia is flying/swimming around (depends on the version) and enter a 5 digit code. The code is found by taking the sum of your money, your ID, and your name's hex value. The first two are easy. The third is a little harder. Here are the steps for the hex value of your name:
1 - For every character(letter/symbol/etc) of your name, there is a number. When you add up the number for every character in your name, you get the hex value.
2 - Use this list (www.oocities.org/ccc1248/pcc.txt) for the hex value (In this case, look under the column "level", since it's actually the base 10 conversion of the hex value) of each number, symbol, etc. It's not a complete list, and it was originally created for reference to the Cinnabar code, so unfortunately there are somethings that it just can't do right now. (numbers, for example)
3 - Do a little adding. When you find the hex value, add it to your money total and your ID number, and the last 5 digits of your sum will be the password (5 digit code). (Not sure if it's last 5 or first 5, try the other if one fails!)
Okay, there IS a site that lets you just to enter the numbers and have it figure it out. It's at:
http://www.bruisebrothers.f2s.com/pokemon/index.php3
As with any code: BE CAREFUL!