Back in the early days of my work at Openmoko, I had come up with the idea to use the standardized USB Device Firmware Upgrade (DFU) protocol for flashing firmware to the Neo1973 and later FreeRunner phones. This encompassed a DFU device implementation that is part of the Openmoko u-boot variant (and has meanwhile been merged in one of the u-boot successor projects) as well as a tool for the host PC called dfu-util.
Since DFU is meant to be device and vendor-agnostic, I tried to code closely to the spec. This meant that it in fact was compatible to other devices, and some folks e.g. used it to flash firmware into their USB-Bluetooth controllers from CSR.
However, there never was any official information how to use dfu-util outside the context of Openmoko, and even more specifically: There never were any official releases.