No$GBA offers DS emulator
Still no sound or WLAN support.
If emulating the Nintendo DS is something that interests you, you might like to know that the guys at Nocash have finally launched their own version, promising "almost full NDS support" including 3D.
What's missing - aside from the obvious lack of touch, voice and rasping breath control mechanics - is sound and WLAN support. That said, the wily programmers at Nocash don't seem to think it'll take them long to crack either function, and a new version will be made available as soon as they've sorted it.
Nocash are claiming this as the first DS emulator running commercial ROMS, though that's already been countered by reports of successful emulation elsewhere. Either way, it's there if you want it. Just don't go using it for any unscrupulous and potentially criminal activities. Please.