The #wemos D1 R2 #arduino #uno #compatible #board sporting an #espressif #esp 8266 is still pretty cool, despite being quite old now. I have mine currently #powered from a super old #lipo via the #input , which should at #minimum accept 6V, running happily from 4.2V or less. A very impressive little device!
Very cool #air #water #pressure #powered #engine by #tomstanton https://youtube.com/watch?v=1Zf_2CZV6Zw