MicroPython on ESP8266
I got a cheap Espressif ESP8266 development board recently and reworked some of my previous Arduino projects. Comparing to Arduino Mega ATmega1280 that runs at 16 MHz + 8 KB of SRAM, ESP8266 is more powerful and feature rich. It integrates a 32-bit Tensilica MCU reaching a maximum clock speed of 160 MHz and a built-in Wi-Fi stack.
The dev kit ships with an eLua based NodeMcu firmware so I have to refresh a MicroPython firmware.