Well... If you REALLY want to get complicated...
Then you could have a field that would work like the fun metal rod where to stick your hand on one side and your hand pops out of the other.
Except each would have a hydraulic on it. then you could have preset feild and you click a button. THe rods change and presto. You have a new field in a matter of minutes.
The problem... Money... not to mention to hole to fit the hydraulics...