Hi ho!
This is my very first Arduino project so please go easy on me 
It's a camera slider with a stepper motor and it is controlled with an Android app through Bluetooth.
It includes:
- Arduino duemilanove
- NEMA 17 stepper motor
- L298N motor controller
- Adafruit Accupack
- HC05 Bluetooth module
- Makerslide rail and carriage (and nuts and bits and wheels and stuff)
Right now the Arduino is powered from the Accupack and the L298N gets 12v from an external power supply. I wanted to build it as mobile as possible so I mounted everything on the carriage, leaving the most possible space for the camera.
The L298N is mounted on the outside of the clear case because although it fits inside the case it was incredibly tight and I was afraid it will melt everything to a soup in there.
I still have to get a battery to be able to get rid of the wall plug and make the slider really awesome.
The construction is pretty solid so far and the results are also satisfactory. I have to work on gradually speeding up the motor to avoid the jerk when it starts to move.