After my first attempts, I really wanted to get a professional result for my next key and I think I reached that goal.
This time, I studied a lot the shape of the sitck and the arrangement of clockworks and gears (two watch movements were used in this one). When I got a good idea of what I wanted to make, I started to sculpt the wood shell and paste the gears on it. I also made a cap this time and I used two metal locks to hold it in place.
After I finished my work I put a coat of varnish but this one was really too glossy and I had to remove it.
Here is the final result: A 4GB mechanical USB Key.