Arduino "piston" device
It sounds like this is nothing to do with an Arduino, just a general Electrical/Mechanical engineering question that you want to control from and Arduino. 
I think you wan a device that when signalled by your Arduino can extend itself by up to 2 inches.

If that is right then I think what you are looking for is a Linear Actuator.  There are plenty out there and some do handle the small stroke you want, but most of them appear to be 9 to 12V.  This means you would require a Darlington transistor or relay to control them from an Arduino.

If you require an extremely precise stoke length then I would recommend a stepper motor with a screw axel.  This would allow you much finer control over how far you pushed, but it would impose limits on what you could do and how it could be mounted.


Can you provide more details on what you want to move?   
List item
Is it heavy? Do you need lots of Torque?
Are you pushing straight or do you need to push in an arc (i.e. a door)?  
What voltage supplies do you have available? 
How fast do you want it to move? 
Do you want it to move exactly the same distance every time?


The more info you can provide the better, but in answer to your original question Yes, it sounds like there might be so you plan is still on the rails.