The Nintendo e-Reader is a sort of code scanning device for the GameBoy Advance that allows for data, and even software, to be distributed on paper cards and read into the GBA. Official uses of the reader have included interaction between collectible trading cards and Nintendo GameCube games (via another cable from the GBA to the Cube), and distribution of entire mini-games for the GBA on said cards.

The dot-code interface has finally been reverse engineered, resulting in the first hobbyist-created e-Reader game. Card data and video are available.