FFVIII for me, because it's pretty much perfect. The trippy sequences, the really well done FMVs (complete with Eyes on Me and the brilliant Ending Theme - the bit where the former segues into the traditional Final Fantasy theme and the credits roll is a real favourite of mine), the camcorder bit at the end. It's sometimes funny, sometimes touching and just fantastic. Especially after the excellent final battle with Ultimecia.

That said, I always enjoy FF endings, the ones I've seen all have something to recommend them.