There is a plethora of research out there supporting cross-curricular education, and Google Lit Trips are one marvelous example. Created using Google Earth, the trips are a collection of links and pictures that follow a particular path. For example, you could follow the Joad family through The Grapes of Wrath (created by Jerome Burg - founder of Google Lit trips) or Possum Magic's Hush through the Australian Outback (created by yours truly).
Under the hood: You must have Google Earth installed on your computer to begin with. The trips download as .kmz files - which you can open inside Google Earth. You can choose the "play" the trip and have the slides advance automatically; or you can manually click through the path locations to allow for more discussion time. If you'd like to create your own trip, click on download and then "Lit Trip Tips." Once it is complete, submit it to Mr. Burg for publication!