A method for accessing locally stored data at a client site via a network request issued by a client browser of a user includes, with a proxy component at the client site, integrating the locally stored data into a placeholder portlet; and providing the portlet including the locally stored data to the client browser in response to the network request. Another method for accessing locally stored data at a client site via a network request issued by a client browser of a user includes providing a placeholder portlet to a proxy component located at the client site; where the placeholder portlet comprises content from an external service provider and is configured to integrate the locally stored data with the content from the external service provider. An electronic data processing system for accessing locally stored data at a client site includes a proxy component configured to intercept requests for access to the locally stored data that are addressed to an external portal server. The proxy component accesses the locally stored data, integrates the locally stored data with content from the external portal server in a placeholder portlet, and serves the placeholder portlet, including the locally stored data, to a requesting client computer.