New-to-me free little Mac utility will map the WiFi coverage in your home/office. It’s pretty neat too and easy to use: you just walk from place to place in your home, with your laptop, stopping to tap where you are on the map. From there the software scans all wireless networks available and notes the connection strength. You can then visualize that data on a network by network basis.
Perfect for deciding if you should add in one of those hot new Airport Express stations, or if you just should move your Time Capsule out of that cabinet you keep it in. ((I really need to move it out of that cabinet…))