Hi R|krdo, You are right about the memory card. I have a device called the "Mega Memory Card" that allows you to back up Game Boy save files. It does not work with the GBA, but any original Game Boy or Game Boy Color games that have a save system can be backed up on this device.

Once you back up your game, you can replace the battery, start a new game, or do anything you want. You can load the backed up save file back into the Game Boy cartridge any time you want. This is real useful if you want to start a new game without loosing your old game save.

You can find this device at Amazon at this address:
http://www.amazon.com/Mega-Memory-Ca.../dp/B000MQ5X4A

One Warning: Do not use this device when your Game Boy has a low battery. Since it uses more power than usual when it backs up or loads a saved game, it would be more likely to shut off the Game Boy if the batteries are low enough. If it gets turned off while it is transferring data, there is a chance that it will wipe all the information out of the Mega Memory Card, so you will loose all your backed up saves. This happenned to me once, so now I always make sure I have a good battery level before backing anything up.