Buy a land somewhere in a developing world (a sharing with a native) and build an apartments for rent (hotels, flats, depending of location). In some areas of China or Brasil it is too late (too expensive), but the developing world is really big. Several projects, $100k+ each.

World's population is growing exponentially. Tourism (flights) becoming cheaper, etc.

In each small town in Himalayas I visited there were a lot of opportunities.