access to restricted uri denied - ajax calling web service

I am trying to create a custom web control and/or avoid using a custom web control by only using javascript as an embedded resource to be reused across multiple sites.  I am trying to avoid using a web control and merely point to a javascript resource so I won't need to declare the webcontrol value across the sites.

When I make a call to the web service, I get the dreaded "access to restricted uri denied" b/c the web service is not in the same domain.  Does anyone have an example to call a web service, not using the ScriptManager/ServiceReference wrappers, to call using straight up AJAX to call a web service to avoid the access issue, probably specifically pointing to a proxy?

 
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