I remember a game named Dungeon Master where spells where made of a combination of several glyphs. The first one indicated the strength of the spell, the second one indicated the element involved (fire, air, water, earth, creatures or the void), the third one indicated an action and the last one was the magical realm involved. For example created light wich lasted a long time, was for the big fireball, gave life potion...
So if your system is logical enough, it would not be hard to guess what are the correct combinations... I remember my pleasure at finding a spell myself instead of finding the scroll the formula...
In my opinion the potion system in Daggerfall sucked because you could not guess the correct mix to achieve the effect you wanted, if a game had this kind of system for potion, spells or whatever, I would run for it immediatly

Dungeon Master and the sequel are two of my all-time favorite role-playing games. The runic magic system didn''t make any sense, and it wasn''t applied as well as it should have been (spells were limited to specific combinations, so you could guess thousands of rune combinations that did absolutely nothing).

Still, mixing ingredients/runes/vital organs and watching the results is always fun, as long as every combination does something. I doesn''t even have to be anything useful (e.g., "Your hair turns blue"), but it should do something.

Writing a story based on this process would be fairly simple, even if it is somewhat cliched. "Evil sorcerer casts powerful spell on kingdom. You must find a counter spell by searching for rare magical ingredients on faraway island." And so forth.

It''s a start, anyway.

I think I didn''t made myself clear enough ... what you need is not a system where you can try *randomly* to find interesting things. But rather a system that make sense in itself. A system where for instance, the user manual would explain the basics, and the player, either through experiment, or through NPCs would learn new things. If you clearly establish in the game that sulphur is a symbol of fire, and that alchemy works on the symbols of different elements. Then you would try mixing Sulphur with different ingredients until you reach the effect you wanted, or some other. It''s not like having a yellow powder, and a black one, and mixing them to see a yellow and black powder.
There has to be some sense in all this, otherwise the player don''t feel the same pleasure of discovering something.
It''s much more gratifying to discover something through reflexion than through mere luck