In 2003, Nintendo released the completely redesigned Game Boy Advance SP which, most importantly, added a front-lit screen, attempting rectifying the one major problem people had with the original GBA. Recently, Nintendo released yet another GBA varient, the Game Boy Micro, with a small and sleek design aimed in large part at an older, iPod-totting audience.
While essentially both titles were or offered multiplayer capabilities, you had to know someone with the game cartridge (Four Swords) and a GBA plus connecting cables.