On November 13, 2003, Nintendo announced that it would be creating a new console for release in 2004. Nintendo stated that it would not be the successor to either the Nintendo GameCube or the Game Boy Advance, but rather it would be considered a 'third pillar' alongside the other two consoles. On January 20, 2004, the console was announced under the codename 'Nintendo DS' (which stands for Dual Screen). Nintendo released a few details at that time, only saying that the console would have two separate 3-inch TFT LCD display panels, separate processors, and up to 1 gigabit of semiconductor memory. Nintendo president Satoru Iwata said, 'We have developed Nintendo DS based upon a completely different concept from existing game devices in order to provide players with a unique entertainment experience for the 21st century.' In March, the codename was changed to 'Nitro' and a document containing most of the console's technical specifications was leaked. In May, the codename was changed back to 'Nintendo DS' and the console was shown in prototype form at Electronic Entertainment Expo (E3). All of the features of the console were revealed by Nintendo at E3. On July 28, 2004, Nintendo revealed a new design, one that was described as 'sleeker and more elegant' than the one shown at E3. Also, the codename 'Nintendo DS' became the official name of the console that day.
The Nintendo DS bears a striking resemblance to the company's first handheld, the Game & Watch, specifically the multi-screen versions such as Donkey Kong.
What's it worth? Take a look at this Nintendo Ds price guide: sold listings for a value indication.