I run a dynasty league where we use auction drafts and auction waivers with money that carries over from year to year. As the commissioner, we allow trading of FAAB for players and it is vastly important in our league for FAAB to move hands. Fleaflicker allows adding players and picks to trades, but why not FAAB? I'm sure there are plenty of leagues that allow trading of FAAB and allowing GMs to add this into trades would make the commissioners' lives much, much easier!