A couple years ago I learned about how Mayan ruins which were previously unknown to archaeologists are now being discovered with satellite remote sensing techniques. The geologist in me thinks this is really cool. Basically, the limestone buildings they constructed has affected the vegetation that has grown on top of the buildings. That vegetation stands out from the rest of the jungle when viewed in infrared. The videos below both discuss the first discovery of this technique, and hint that this technique could be used to discover many more sites. This obviously is exciting because the Nephites and Lamanites were part of the Maya civilization.
NOVA video: here
National Geographic Video: here
NASA article: here
Maps (thanks to Larry P.): here