The concept for this came while reading TB's recent Facebook post about r60 that included "There's a whole new class of items among them, too (staves as an extension of wands... the difference here is that they don't have actual charges but recharge after a certain amount of time has passed; maybe moves instead of time - I'm still thinking about balance issues related to the wilderness)."

I got to thinking, what about items that use a completely unusual charging mechanism? Items that, when wielded or worn, took a share of the PC's regained PP and stored that as their own charge, which could then be used to create magical effects. They would be most suited to half-casters, by design and intention, for two reasons:
1.) They only recharge when the player's PP actually goes up. Characters who don't use any magic never expend PP, and never restore it. Non-casters would get no benefit.
2.) They reduce (the rate? Quantity? Whatever is balanced best) of the PC's PP regeneration. Full casters would find the PP regeneration penalty to be dangerous, since full casters live and die by their PP reserves.

The ideal users would be half-casters, who have and use spells but are more than capable of holding their own in non-magical combat. Using spells at a reasonable rate would maintain a usable charge, allowing them access to bonus effects.

Probably include a drain-over-time mechanic to prevent spending lots of PP on bad spells in town to build a huge charge. Maybe like 1% of current charge per game minute. They'd mostly drain while moving through the wilderness.

At the moment, this is nothing more than "just a thought." If the general populace doesn't like it, if skilled game designers feel it's poor design, if coders think it's too much work for the benefit, I won't get butthurt. XD