There appear to be several tutorials on going the other way, but I wasn't able to find the solution I needed. With a little tinkering, I found this to work (pretty straightforward really):
If the C# script you are trying to access is called Foo
var bar = gameObject.GetComponent("Foo");
Quotation marks. That's it. HOWEVER, what if we are using #pragma strict, or making this for iPhone? The above code will most likely create problems since either of the situations requires everything to be explicitly typed. So, if Foo where a javascript file, you could do something like:
var bar : Foo = gameObject.GetComponent(Foo);
Pretty simple. Now, try that with a C# file. No luck? That is because of the compilation order that Unity uses. Trying to use "Foo" for your type won't work either. To fix this, you will need to force Unity to compile the C# file first. This can be done by putting the C# file in the folders "Standard Assets", "Pro Standard Assets" or "Plugins." There are, of course, some caveats of doing that. More information Here
So, once you have moved your C# file, you should be able to declare your 'bar' variable as follows:
var bar : Foo = gameObject.GetComponent("Foo");
#pragma strict creates some other interesting quicks that you might not be expecting. More in the next blog post about that.
