There are devices out there which make dumping ROMs a breeze, but what if you're handy with tech and fancy taking on the challenge yourself?
That's precisely what Francis Stokes of Low Byte Productions has done (thanks, Hackaday). Using the Game Boy's link cable – you know, the old-school way of enjoying some multiplayer action – Stokes has been able to dump game data.
The process isn't as straightforward as that sounds, of course. First, Stokes has to execute some custom code on the Game Boy itself via a Flash Cart. Once this code is loaded into the console's RAM, it remains there until another cart is inserted, at which point it prompts the user to dump the ROM. The code then sends the data over the link cable to a Saleae logic analyzer.
This is such a delicate process that Stokes even discovered that the length of the cable could cause errors due to the amount of outside interference experienced with a longer lead.
If you fancy giving this a go, you can find Stokes' code on GitHub.