You know, back when Zak S posted a way to assign keys randomly to doors (roll d100 to assign a key number, that's the percentage chance that key belongs to a given door,) and I elaborated on that with a way to use key words as numbers, using Lewis Carroll's mnemonics, I meant to say something about other exotic ways of using that same method. For example, herbal cures for disease.
During a wilderness expedition or trip to the local bazaar, one player wants to role-play their cleric or druid character's fascination with herbs and plants; you have nothing prepared, so you use the Random Random Table linked above to assign two letters and use that for the plant's name (stinkwort, gladberry, hoodfungus) or description (blue petals, yellow thorns.) Later, someone catches a disease or parasite, and the player says "I give the patient a tea made from stinkwort." Does it help? Translate the name back into numbers, use that as the chance that it will aid the disease. From now on, both you and the player know whether that herb works on that disease. If the disease has an unusual symptom (green pustules,) use that as the disease's "key", using the lowest number of the two keys, or multiplying/adding 10 if the herbal key matches the disease key.
I'd probably only use the first letter of the herb's keyword as its "number", since I would use the Target 20 method I outlined in my previous post; thus, stinkwort would have a +6 chance to help disease, while gladberry has a +9 chance. Once a curative works on a given disease, it is locked in to all diseases of the same type: curing someone's skin disease with gladberry means it only works on skin diseases.
"Help disease" is defined loosely. I'd let herbal remedies cure mild diseases outright, reduce the penalty of more serious diseases temporarily, and give a save bonus on recovery (+3 for severe, +2 for crippling, +1 for fatal.) If the disease has a keyword, there's no save bonus unless there's a keyword match.
There's a couple other ways to use those keywords that I'd like to write about later.