Nanoloop (by Oliver Wittchow) is a real-time sound editor for the Game Boy Advance:
Nanoloop is a synthesizer / sequencer for the Nintendo Game Boy systems. Stored on a normal game cartridge, it allows to produce nice electronic music without further hardware, using either headphones or an external amplifier (home stereo, active speakers, etc) as sound output.
Why do I blog this? that seems to be a curious tool to turn a portable console into a musical device. I like things like that, when an artifact is détournée.