I would have added the rest of the Mana series as well as the Kingdom Hearts series, but the number of poll options is limited to 20. As it is, I simply listed all the spin-off games that either explicitly used FF characters or places (like the Chocobo games, Ehrgeiz, and Vagrant Story) or had FF in the title. Also, I only listed games released in English and omitted mobile phone games (because I hardly consider the latter to be games, anyway).

EDIT: Did the Ehrgeiz arcade game have the FF7 characters in it, or were they added for the PS1 port?