A simple option to let classes gain some skill points or raise their base attack bonus without bothering with multi-classing or tinkering with the rules too much.
CROSSING CLASSES
Upon leveling up a Fighter could sacrifice their +1 to attack for 2 skill points.
A Specialist could sacrifice their 2 skill points for a +1 to attack.
A Cleric or Magic-User could sacrifice a spell slot for either +1 attack or 2 skill points.
Fighters and Specialist cannot gain spells this way.
