I can really only remember one. It was supposed to change a tile by the secret entrace Locke shows Terra after the Narshe Guards and Megalodoths vs. Locke and the Moogles battle, to the left of the Adventurer's School. It made a tile near the heap of mountains smoother looking.
I think I got there from GameFAQs, but I think it was before archiving.
EDIT: OK, there were two left off the list I made up there (obviously not intentionally). First was Imzog, and obviously he doesn't have what I'm looking for, but I noticed he has a link to NovaliaSpirit's website. Hearing that name makes me think it had to have been his site I got these patches from.
However, I try to go to the website and it's ka-dead. Oh well.
While I'm here, do you guys still have that list of FFVI bugs hosted at Slick Productions? I'm bored and I need a good read.