These function like low-power rods, since they regernerate spell points much slower and can cast fewer times before running out.
The list of spells is a lot more geared toward utility and infrequently-cast spells, such as summon <elemental> and dark vision for that reason.
Currently set to be pretty rare. If it turns out these should really be more common than rods, it can be done.
git-svn-id: svn+ssh://svn.code.sf.net/p/crossfire/code/arch/trunk@21843 282e977c-c81d-0410-88c4-b93c2d0d6712