Sometimes you have to ask why – why would someone jam a movie into a Game Boy Advance cart to watch it on an ill-fitting screen (for movie viewing)?
The answer is, because they can and are clever enough to achieve this feat! Our eyes are already in panic mode just at the thought of watching a movie on the Game Boy Advance screen at 4 frames per second, but we are so glad that Wulff Den took the initiative and time to create these darn cool and unique GBA movie cartridges.
source: Wulff Den