Permanent STR Stat Gain
Get a Sovereign to level 10 and put a point into Fire/Freeze/Shock arms. Cast the spell on a member of your party and it temporarily raises your STR by 3. Casting again will temporarily increase by 3 again, but permanently increase by 3 as well. This can be done until that party member has 999 STR.
Unparalyze Allies
Want to remove paralysis without wasting item or TP? Simply walk into that character with the leader. They'll swap places, instantly removing the paralysis. Works at any time in the dungeon.