NDSwelt, an 'inofficial' online magazine (in German) about the Nintendo DS has an interview (in German) with Andreas 'Mrsid' Varga about homebrew programming for the Nintendo DS in general, and his port of Great Giana Sisters in particular (watch a video here).
Giana Sisters is a famous game in the history of game development in Germany, not least because of Nintendo's legal pressure. Armin Gessert, the programmer, went on to found Spellbound Entertainment and develop Desperados. Manfred Trenz, the graphic artist, later created the Katakis and Turrican series, doing not only the graphics but also the coding. He also created the mythical Rendering Ranger, a game for which I'm in the credits at Mobygames but which I've never seen in its finished state. It was only released in Japan as far as I know.
I've had the pleasure of working with Andreas at Rockstar Vienna. If he ports Giana Sisters and Descent to the DS in his spare time, you can imagine the kind of amazing things he does at work. In an ironic twist of fate, he is an Austrian working in Amsterdam (for Guerrilla Games on Killzone 2), while I am a Dutchman working in Vienna. It is only a matter of time before his Dutch is as good as my Austrian.