Feats to make unarmed strike deal slashing or piercing damage?

[IcyCool]

The title pretty much says it all, but are there any feats (or other methods) for allowing an unarmed strike to deal slashing or piercing damage?

 

[Crothian]

I think there was an epic feat that did something like this.

 

[Darkness]

Versatile Unarmed Strike (PHB II).

 

[saucercrab]

I think there was an epic feat that did something like this.

Yeah, Vorpal Strike.

Also, the initiate of draconic mysteries PrC in the Drac can do slashing unarmed damage, IIRC.