My project over the past few days: A WiFi temperature sensor. I’ve been wanting to play with the ESP8266 WiFi module for many months now. Its super cheap and (thanks to many other makers hard work) easy to program using Arduino software.
I needed some reason to use it and remembered that a friend of the family gave me this photovoltaic cell/battery pack a while ago. I finished wiring it up last night and started testing it. It made it through the night on partially charged batteries, and is taking a charge out under the partly cloudy sky today. I could easily use a host of other sensors as well.
Welcome to the New World of ESP