Grogg of the North
Adventurer
Is there any way to add weapon powers to unarmed attacks? Who wouldn't love have a shocking burst roundhouse kick or vorpal sword hand strike?
An Enlightened Fist (Monk/Arcane Caster PrC) lets you sacrifice spells to do flaming or shocking damage with your unarmed strikes.
MIC has an elixer that lets you do +1d6 fire damage with unarmed strikes for 3 minutes. At 300 gp a pop though, that could get pricey quickly if you want to have plenty available.
IIRC, Pathfinder allowed you to add things like flaming to your amulet of mighty fists.
Finally, a player of mine in games past had a custom pair of gloves that let his unarmed strikes do fire damage. I can't recall what the price was but you could always talk with your GM/Player.