>>11943282
According to Micro64 a lot more games supported the memory card than you think, and some of these had a save that took up the entire thing, or let you easily fill it up with saves for that one game such as ghost data in a racing game.

Would not be hard to add rumble function to something like that today though, depending on cost might even be able to integrate a Transfer Pak into it too (or at least, simulate one by loading a rom into it).