That's nifty, Tytus. I built something similar this summer, and then drew it up in MLCad. I don't have any of the Lego pnuematics, so I did it all with motors, which was an interesting challenge in itself. The left wedge wheel is the output, and the right goes to the shifting motor.
For anyone interested:
4 Brick 1 x 16
3 Brick 2 x 4
1 Electric Technic Mini-Motor 9v
2 Plate 1 x 2
3 Plate 2 x 4
6 Technic Axle 4
2 Technic Axle 8
1 Technic Axle 10
1 Technic Axle Joiner
2 Technic Brick 1 x 16 with Holes
15 Technic Bush
6 Technic Bush 1/2 Smooth
6 Technic Gear 8 Tooth
1 Technic Gear 24 Tooth Crown
4 Technic Gear 40 Tooth
2 Technic Gear Rack 1 x 4
1 Technic Plate 1 x 4 with Holes
2 Technic Wedge Belt Wheel
1 Technic Worm Screw
It's huge and unwieldy, but it works, and it's kinda cool.
