ESP-01 (ESP8266) wireless WIFI transceiver

Got it connected to my home network in under five minutes using just three jumper wires. The 802.11b/g/n compatibility means my temperature sensor data now posts to a web server reliably. For the price, it's an incredible way to add WiFi to any Arduino project.

Small footprint and low power draw made it perfect for my weather station build — it connects to my router without issue. The 802.11b/g/n support is great for pulling JSON data from an API every few minutes.

Finally got my home sensor project talking to the router thanks to this chip, and the 802.11b/g/n compatibility made setup painless. For three bucks, it's hard to beat.