Some time ago me and my former room-mate thought about making a simple but neat remote-controlled power outlet to control house appliances via our smartphone, maybe even when out of our house. The only solution at that time was using a uC and Bluetooth, which has a low range, and interfacing a Bluetooth module to a PC to then allow remote control via the interwebs is a bit tricky and tedious to setup.
BUT! ESP8266 fell from the sky, with its cheapness, robustness, and power, the new HaD Prize came too, and here I am submitting this project and substituting uC+BT+PC with uC+WiFi+WebServer all in a single chip.
The product should be really simple to use: you plug it in and it connects to your router, you then open your browser, connect to its IP address (or your public one), and you will see a web interface that lets you turn on or off the power outlets provided.
The implementation is pretty straight forward: a standard power strip will house everything inside it, the mains cord of the power strip will be connected to an AC-DC power supply that will provide 5 V to power the relay circuit and the ESP8266 (with a 3.3V regulator), hopefully the relay control signal will not need level conversion. The relays will switch the hot line of the mains cord, while the neutral and earth lines will be bused for all the outlets. The ESP8266 on first boot will show a network to which the user can connect; connecting to this network will show a simple web interface to set the parameters of your AP/router (SSID, password, encryption) as well as credentials that will be used to access the actual web interface. When done, it will reset and switch to host mode, connecting to the router the user just configured.
This could be easily and cheaply hacked together, even for an user with little knowledge, or stuffed in a nice ready-made product to be sold for the masses.