Little things you *may* have not known.
When you go to the Gold Saucer (at any time that it is open) over at the Wonder square, the Crazy Motor Cycle Chase that you played at the beginning of the game is available to be played again. You will also notice that Aerith is driving the truck ( though, originally it was Tifa). Aerith is the only one in the vehicle.
At some point on the second disc, you will be able to obtain the key to Sector 6 at Bone Village. Once you have the key you can open the gate to Sector 6 and head into Aerith's church, where you will see her ghost tending the flowers among the two children that are there. However, once you approach her ghost, she will disappear.
As you return to the Alexandria Harbour after it has been destroyed, head to the steeple area. There is a flower girl talking to one of the soldiers, Pluto Knight VIII. Here is the conversation:
Flower girl "He's handsome, but he's not exactly Mr. Personality..."
Weimar, Pluto Knight VIII "To have a chance to meet such a pretty flower like you in a destroyed city..... Oh, I'm the luckiest guy in the world!"
Sound familiar? Hehehe.
Also! When you go to Lindblum, in a weapons shop, go near the weapons on the wall. Zidane will say "I remember a spiky haired guy who carried a sword like this." Or something like that. Go back and he'll say "no cloud or squall." There is also a guy walking around the area, and his name is Locke (from FFVI). And during the play "I Want to be Your Canary", Marcus says "No cloud, or squall shall hinder us!"
Cloud is an anti-virus that can be found in a magazine called Aeris.