Laundry timer for the ESP8266 ESP-01: http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family#esp-01
Prototype photo: https://goo.gl/photos/NjTwntU1QywMau2y6
The only really important part in that photo is the ESP-01 module (and I suppose the display, but even that isn't really needed). The breadboard is only used to facilitate development/debugging and the raspberry pi is just used for 3.3v power :)
This Arduino project requires the ESP8266 board support files to be installed as per http://www.arduinesp.com/getting-started. This also makes use of the TM1637 library from https://github.com/avishorp/TM1637
This simple sketch uses an ESP8266 ESP-01 module as a countdown reminder timer. I frequently will throw a load of laundry in the washer and even when I set a timer to remind me to put the clothes in the dryer, I will dismiss the timer and then forget about it. This will keep sending notification emails until I turn it off.
On powerup it will start counting down from 35 minutes and display this countdown on a 4 digit 7-segment display. When the countdown reaches 0, it will connect up to your wifi network and send an email notification message. It will then restart the counter at 30 seconds and keep sending new email notifications every 30 seconds until you power it down.
This uses an authenticated smtp server account from smtp2go.com. You have to sign up for a free account and then base64 encode the username and password in the source for it to connect and send email.