Your smallest "full size" knife.

[Div4gold]

Leaving the file teeth on part of the blade makes it look cool and if you ever break a fingernail then your covered

 

[ISP 5353]

Shadow Tech makes some cool little knives that may be just what you are looking for.

 

[Stubai]

The humble Mora is your clear answer here. A close second for me would be my SOG Seal Pup Elite. That little pup is a tough customer and feels great in the mit!