Returning results from a page method call

In my ASP.NET AJAX web site, I am attempting to use Page Methods to return data from the web server. I would like to be able to return the value from a page method like so:

function GetValue()
{
    return PageMethods.GetValueFromServer();
}

function ManipulateValue()
{
    var myValue = GetValue();

    // Do something with myValue
}

Unfortunately, calling a page method requires the use of a callback function. I really need to retrieve the value without having to store it in a global variable in the callback function; is there any way to do this?
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