The best innovations are those so obvious that you wonder how we managed to go so long without someone formulating them. Powerline Ethernet was one such inspired discovery, and the format taken by the Devolo dLan 200 AV Wireless N kit is another. Why not take a powerline Ethernet adaptor and embed a Wi-Fi adaptor within it?
The result is that you have the both convenience of Wi-Fi in whatever room of your house that you need it, but the stability of connection afforded by Ethernet in between your router and wherever your computer is. You might just want a good signal in your bedroom, but you could equally extend your house's existing Wi-Fi network out to an office or summer house at the bottom of your garden - it really is a brilliant idea.
Despite the additional connectivity options, the dLan 200 AV adaptors don't look much different from your common or garden variety powerline Ethernet adaptors. The Ethernet-only plug is small enough that it doesn't intrude into the space next to it - a flaw some of these devices do have - and has a single Ethernet port, for connecting to your router. The adaptor that handles Wi-Fi as well is larger, offering three Ethernet ports in addition to Wireless N, but it's not too intrusive.
The Wi-Fi adaptor has a dedicated switch on it for turning this connection on and off as required. While of limited utility for most, we won't complain that the option is there. If a simple on/off ability isn't sufficient control over whether your Wi-Fi network is being broadcast or not, you might welcome the option to set up a timed schedule for its enabling and disabling.
This setup is managed through a combination of some desktop software and a web interface (launched via the software, so you don't have to remember IP addresses unlike, say, most routers' interfaces). Helpfully the desktop application uses Adobe AIR so it works across any platform which that runs on, not just Windows