Dell Vostro laptop that connects wirelessly to a netgear WRT54G v4, latest firmware. Dekstop that connects wirelessly as well. As soon as the sun goes down the laptop either cannot access the internet or it is worse than dialup slow. The local network still works as the laptop can print to shared printers off the desktop. My first thought is some sort of interference but I can't think of why there would be interference only at night and why it only affefcts the laptop and not the desktop.