DSerial is an adaptor for Slot-1 with a couple of different ports available: GPIO, UART, RS-232, USB client, ADC and PWM. This allows to connect NDS to devices like MIDI keyboards, computers, GPS receivers, keyboards, R/C servos, sensors, anything with a serial port and more. The firmware for DSerial is open-source and can be reprogrammed on-the-fly from DS if needed for a particular program.
RoboDS is an open robotic platform for the DS. It runs a minimal HTTP server and can be remotely controlled via NDS Wi-Fi. It is very simple to construct as it uses 3 equal servos (2 of them are modified for continuous rotation). Sensors can be added as needed and connected to DSerial2. I will post a hi-def assembly video shortly.