the post viewtopic.php?f=32&t=5454&p=28670&hilit=external+spi+flash#p28670 has mentioned "SPI RAM too available that you can add externally". Here (https://github.com/CHERTS/esp8266-i2c_24xx32) is sample driver for serial EEPROM from ATMEL and Microchip.
- expand memory for ESP12F via external chip, any one of RAM / Flash (or for both)?
- change MAC address for permanent use?
- save private data (not big) in non-volatile memory? for example, user password, ip-addresses, etc.
- switch wifi power off and do other things to reduce power consumption?
- find latest binaries for Espruino? This post (viewtopic.php?f=44&t=5713) is dated on Y2015, and has bad link.