There is now a new version of the firmware for the Lisp Badge, with the following main improvements:
It includes the AVR assembler.
It uses flash memory for save-image, allowing the whole workspace to be saved to flash.
Get it from GitHub here: https://github.com/technoblogy/lisp-badge.
To use the new features you need to update the ATmega1284P bootloader. For details see: Lisp Badge [Updated].