For $100, you can swap out one of your home's outlets with the Wi-Fi-enabled iDevices Wall Outlet. Make that upgrade, and you'll be able to turn each of its two outlets on and off independently, or program them to turn on and off automatically using the iDevices app on your Android or iOS device. You can also sync the Wall Outlet up with Apple HomeKit or with Amazon's Alexa to turn each outlet on and off using voice commands.
In other words, each outlet functions the same as one of iDevices' plug-in smart switches, right down to the fact that they'll track the energy usage of whatever you've got plugged in. The only difference, obviously, it that this is a hard-wired product -- it isn't anywhere near as flexible as the switch, which you can plug in anywhere.
On the other hand, smartening up your outlets makes for a connected living space that's a lot more seamless than one that's littered with blocky plugs all over the place. And, to the Wall Outlet's credit, it performed flawlessly in my tests at the CNET Smart Home. With just three wires to connect (line, neutral and ground), installing it was a relative cinch, and the integrations with Siri and Alexa both worked as advertised (there's even a little fold-down flap on the front of the outlet with the Apple HomeKit pairing code printed on it -- a nice, thoughtful touch). Add in the energy-tracking feature, and there's really not much else that I wish this thing was capable of.
In fact, I'll take it further: this is the best smart outlet you can buy right now. It works well, it's got a good slate of third-party integrations, it's easy to install, it doesn't need a hub and it's from an established name with a clear vision for the connected home.
Still, this thing is something of a niche product, and an expensive one at that. I can see the appeal for anyone who's ready to go all-in with smart home tech, but if you're a curious connected home beginner, then you're much better off just getting a plug-in smart switch to experiment with. The Belkin WeMo Mini, the iHome Smart Plug, and iDevices' own smart switch all cost less than half as much as the Wall Outlet -- I say start there and wait for prices to come down before worrying about your outlets.