What looks best?

vars.js

/*
 * How do you like your Javascript variables?
 * Is there a PEP8 for Javascript?
 */


// Option 1 
var viewPage = function() {};

// Option 2
var view_page = function() {};

// Option 3
var ViewPage = function() {};

Situation wise, I'd say first one for object instance, second one for function/variable names, and third one for class names.

However I like the second one best for plain old variables.

Option 3 is for classes. Option 1 is for everything else. I think this is the norm.

What you're describing seems to be Python. :)

Yep, in Python I'd use 2 and 3
In Java, C# or C++ I'd use 1 and 3
In C I'd just use 2

In Javascript, I'd probably still just use 2