Hi!
Thanks!
That was a fast reply...and Yes! that is what I like to build somewhat modified for microbiology work instead of woodwork,but still the principle is the same. Stepper motors is of cource nice but I happend to lay my hands on three 360 continous rotating servos (fun but tricky to program)...and I dont have stepper motors yet...still searching among laboratory equipment 
(I need an Igor..)
And I still need to get ideas on how to wire the arduino (ok! three servos..not that hard but still I need some basic code...preferably with x,y grid in the "software"). I have just dived into the programming part with Processing(so far has everything worked)
The mixing device have during the writing "arised from the dead" (live,live!!!...rotate45,go back rotade 45...hahahah...Arduino is fun for i biologist like me...)
Now Im thinking of a sensor that measures the growth of the cultures, turbidity or spectrophotometric hmm...(LED,LDR,optic filter and some tubes)...lets find some more stuff...
..and Im going to search for an Arduino supported 3 axis CNC...and some processing code.
Thanks again...