with WDS, you can get a second unit and put it at the other end of the house, within range of the first. Set up WDS. Get a third unit, put it in the shop. So on, so forth. They talk to each other.
Now your laptop can connect totally seamlessly anywhere from the front of the house, to the shop. It will keep the same IP address. It will always be able to connect to any computer on your network, regardless of which access point it is "connecting to" at the time. You can also use the wired ports on those remote routers to connect other wired computers.
The caveat:
It shares the transmission bandwidth. If you have a good connection at 36 Mbps, you will get half that between the laptop and a computer hooked to the router. The other half is used getting your traffic across the Wireless Distribution System.
For surfing the net, this is totally unimportant. For moving large files across the LAN, It will make a difference.