with R4, M3, CycloDS or others thinks like that you can play emulators (NES, SNES, Mega Drive, Atari), you can play .avi videos, downloaded imported games, run user-created programs, etc... PSP have a firmware that can do this too.
They should enable this features (run 3th part programs) by default, so R4 would be usefull only for piracy, with is a good argument for banning it.
Consoles are worthless without unlock devices, they just play games...
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