Worlds of Ultima: The Savage Empire - Ultima Underworld

 
In Ultima Underworld I & II there is an odd cheat that my cousins and I discovered by accident.
 Take a potion or scroll. Fireball it once. (Yes I did say fireball it.)
 Now you would think you have just wasted a perfectly good item because it is now just debris, but you're wrong.
 Pick it up and use it. Believe it or not, you should now have infinite uses of whatever it used to be.
 Amazingly it works. Debris are your friends. The real problem is organizing them all.
 -Arah J. Leonard AKA Zeus's Pet Rat