I think it might be possible to have the ESP8266 inside a cartridge, with an Atmega16A faking to be a dual port (SPI + parallel BUS) SRAM and the ESP8266 faking to be a memory bank controller. This way I could grab data from the web, put it into "RAM" and read it out with the game boy. This way I could also get rid of the dongle ESP idea. Some protocols would have to be written and thought out. Feeling very yoda-ish today. Gotta eat sth.