Driveway alert system

When my husband built the house the main thought was energy conservation. Regular walls are four inches thick. Our house walls are ten inches thick. It's great that we don't have a high fuel bill. We have small windows in our house to also conserve heat loss. The only problem is you can't see the driveway very well. The other day my husband installed a driveway alert system which flashes a little light inside of our house when somebody pulls in. It's wireless. We screwed one part to our mail box to focus on the end of the driveway. The other part you just plug in to an outlet in your house and you're done. Talk about easy installation.