Calling a function from a different script on the same object

Okay, this goes down to OOPdesign, maybe, but say I've developed two independent scripts, in this case, Gravity and a player controller. I add both to a gameobject, and one of the features of the game controller dynamically alters the gravity script variables (think: tractor beam, basically I increase my gravity range, and then temporarily change the mass of my rigidbody)

My question is, what is the best way to call a function in another script that is on the same object?

I got it working by going something like this.SendMessage("SetGravityRange",1000);

but is that the right way to do it? It doesn't feel quite right, and while I don't want to combine it in the same class, I kind of feel like I should be able to do a using Gravity; or Gravity.SetGravityRange(1000); sort of thing (realising that neither of those work).

Does anyone have any thoughts? Thanks, Mike