Tutorial 1: ESP8266 with DHT11 Temperature and Humidity Sensor using Arduino IDE---https://microdigisoft.com/esp8266-with-dht11-temperature-and-humidity-sensor-using ...
[ladyada] has a freshly-published and amazingly thorough tutorial on passive infrared (PIR) motion sensors. Most often seen in security floodlights and automatic doors, in creative hands these sensors ...