White Wind: Healing spell that restores half of your current HP and gets rid of any negative status effects.
it actually restores HP equal to the amount of HP the caster has. ie, if Cloud with 5000 HP casts it, the entire party will be healed 5000 HP. its useful for everyone to have an enemy skill materia with white wind, so in a bind, anyone can be a good healer as long as their HP is high.

another great skill is Magic Hammer. learn this by manipulating the razor weed creatures around wutai. this skill allows you to steal/take 100MP from an enemy. until you have the ability to obtain lots of turbo ethers, this is a great skill to have.

another skill to learn while your around wutai is the death force skill. manipulate the giant tortoise on the beach area. this makes you immune to instant death, like the stab attack from a tonberry (not everyone's grudge) which appear in the battle arena sometimes.

there are some better skills too, but i wouldnt want to ramble on.