This is my first attempt at a Sarrus linkage suitable for a Z axis. It has room for a skate bearing, 10-32 threaded rod, and 10-32 nut to drive it. In practice, this mechanism is not quite stiff enough for good printing, but it might be useful for other things.
The total range of movement is just over 100 mm.
Print one each of the end plates. Print 4 of plate_a and 4 of plate_b. These have an overhang, but using the 'support on exterior only' setting on skeinforge gives workable results. Also, the plate_ab_merged file allows you to print the hinge plates in pairs.
Chase out all the small holes with a 1/16" drill bit, then use 1/16" brass rod to make hinge pins.