This is by far one of the most overabused glitches in this game. This glitch allows you to duplicate any item. That is why it is so overabused.
How to do it Edit
Select an item and confirm that you're going to use it (do this to an Item that you want to duplicate). When you select your second item, instead of confirming that you're going to use it, cancel and pick the item again. Each time you do this, the first item that you confirm will go up by 1. Continue as long as you like to get 99 of every item.
This is by far the easiest and fastest way of getting 99 of items, and the only way to get 99 Dragon Fangs.
NOTE: if you cancel with (square), instead of X, then W-Item duplication will not work).
Credits and acknowledgements Edit
- Xenomic and NorseFTX for their Final Fantasy VII glitch guide on GameFAQS.
- Myself for begging my sister to let me try out the glitch and eventually confirming it.
- My sister for letting me try it out.
http://www.gamefaqs.com/console/psx/file/197341/45711 - glitch guide on GameFAQS
Happy glitchin' :p