Solar Light Address Markers
Address markers come in a huge variety of styles. These types of solar lights can fitted to a wall, gate, window (via suction cups) or sometimes come with stakes that fit into the ground. This quality unit I have shown here can be seen at a distance of up to 100 feet, and has 3″ tall numbers.
Most units are weather resistant with automatic dusk till dawn functionality and you could reasonably expect fifteen hours of operation from a single charge.
Solar lights of course have the added benefits of energy conservation and economy.