Zenny Cheat
When you're inside the shopping center, you'll see a tin can on the ground. If you kick the can into the Jetlag Bakery, you'll receive 1,000 Zenny. You can do this as many times as you wish for unlimited Zenny, but it has a negative effect on Mega Man's reputation.
Help With Enemies
If you hold "L1" or "R1" while jumping or rolling to the side, Mega Man will become momentarily invincible. While you're in the ruins, you can manipulate the camera to check for enemies on the opposite side of most closed doors. When you're standing in front of the door, rotate the camera in one direction until you can see into the next room.
Unlockable Difficulties
To unlock the "Hard" difficulty, complete the game, and then return to the title screen without resetting or turning off the PlayStation. This new game mode will be under "Options." Completing the game on the "Hard" difficulty will unlock the "Easy" mode. Return to the title screen as before, and the new difficulty will be under "Options." You'll start the game with Jet Skates and full capability for your left arm weapon. You'll also earn more Zenny for defeating enemies.
Getting Zenny From Data
When you're inside the Flutter after unlocking the Central Gate, you can get free Zenny from Data. When you talk to him, choose to say "I keep losing fights," and you'll receive 100 Zenny. Data will then ask if you need more. If you respond "No, thanks," he will give you 1,000 Zenny. After that, when Data asks if you need more, continue to answer "Please," and he'll give you increasing sums of Zenny each time you do. Once you receive a total of 56,100 Zenny from Data, you can't get any more.
Free Sodas
You can get free sodas from the refrigerator inside the Flutter. You can also get a soda from kicking a vending machine, but doing this more than once will destroy the machine and lower your reputation.