if thar be a Final Fantasy X-over (crossover)

I've been spouting, rambling, ranting, touting the idea of a Final Fantasy that plays like Star Wars Battlefront.
Psychotic has mentioned he'd like to see a Final Fantasy in Lego style.
Monty Oum has already combined Final Fantasy with Dead or Alive in a fan project.
Final Fantasy has been combined with Disney via Kingdom Hearts.

The question here is: What crossovers would you like to see?

Whether just using the gameplay from a title or to combine the casts, there are no rules for crossovers save one: be serious. Don't list something just to list. If you would legitimately like to see it, then fine, but don't say something like Final Fantasy Lottery.