Useful Spells To Store In A Major Artefact
Another thread on this forum led to a train of thought, and I suddenly realised that Dispell is probably one of the most important spells any mage can learn. This makes the Store (Neutral IV) spell so useful during an adventure, because it would allow Dispell to be cast nearly instantly in the field.
Likewise, Well of Anasiron, Suld's Ward and such other useful spells could be put into Stores (or the Vessel of Iladan (Neutral V), if there's enough capacity).
Which spells would you consider to be most useful for a Shek-Pvar in the field, important enough to store them in an artefact for rapid casting?
Storable Spells
As I'm sure you know, there are many, many spells which would be very handy Stored or placed in a Vessel of Íladan, but the following few neutral/common ones strike me as especially useful:
Feel (common, multilevel) - detecting enchantments is quite a basic function that you might need at any time.
Zýna's Tap (neutral, level II) - getting rid of pesky fatigue for a short time may well be a sudden requirement...
Maintain (neutral, multilevel) - suddenly needing to stretch out a spell duration can happen to anybody!
Well of Ànasîron (neutral, level III) - a general counterspell may be handy at any time.
Dispell has already been mentioned, and several others could be very useful (Ear/Tongue/Mind of Pvâra, Abort, Absorb, Attune, Infuse, Violet Eye, Hlándor's Flash, Balm of Grésan and Will of Kîrat all spring to mind).
When browsing and checking out spells for this, by the way, I noted the wording in Periapt of Power (neutral multilevel spell on page 'Grey 18' of SP 3.0) about "When all EP have been expended, the periapt is effectively dispelled (although a faint 'residue’ may remain for years)." This tends to support the idea of residues outlasting their inciting spell, I think.
Periapt Residue
That residue thing is just to prevent the Periapt from being recharged after it has been expended. Periapt is supposed to be a "one and done" enchantment, and the author took pains to make it non-rechargeable. Balm of Chesme is meant to be reusable, or otherwise it'd have just halved Chesme's lifespan by two months and that would have been it.
The residue on Balm of Chesme is just to prevent gamers from casting Balm on their characters over and over for a month and coming out with a lifespan of 10,000 years or something.
Residue of Spells
You can suppose all you like, but the rules don't actually say any of that (so each table can parse it as they wish).
Edit: on top of which, the most you will ever get out of casting Balm of Chésmè multiple times at once is a lengthening of life by one year. The spell slows ageing for the duration; the durations don't stack and the spell doesn't subtract age, so over the 1 year duration of a CS you won't prevent more than a year's ageing, no matter how hard you try.
Misinterpretation
I really don't think that's how to interpret the spell. It's there to stop newbie minmaxers glutting on the spell and giving themselves 10,000 year lifespans at the start of the game.
I bet Dispell could remove the residue from an exhausted Periapt, meaning that the mage can refill it at any time after it's discharged its last EP.
Interpretation
Read the spell. "Minimaxers" could not "glut on the spell and giving themselves 10,000 year lifespans at the start of the game" under any valid reading; the spell lasts for a maximum of one year and only slows ageing. You can't do more than gain a year less ageing in the first year of the game, no matter what you do. The spell as written will simply not do it; the durations don't stack.
I'm sure that Dispell could remove the residue from a used Periapt - and also from someone who has residue from Balm of Chésmè after the spell has ended. It can remove Indefinite effects at ML 81+, even if you deem the residue Indefinite.
Incidentally, if you want to minmax Balm of Chésmè you cast-dispell it until you get CS, then you Maintain it (with a Level VII Maintain spell).
Some interesting comments
Some interesting comments here. Much to think about.