If you became an assassin...

[DaveB]

Use a bullet made of super-cooled ice. Melts in the body afterwards. No trace.

Doesnt work. It's been tried and the bullet just disintegrates in the barrel when fired

*cough* apparently *cough*

It all depends on the message you are trying to send. Do you want the target removed with the minimum of fuss and mess or do you want an example made of them?

For the former a single clean gunshot or a knife followed by disposal of the body. For the latter, tie to a chair with *lots* of rope then use a large axe. Repeatedly. And a note pinned to the remains saying "Don't do it again."

Personal favorite is a coke can filled with semtex with the detonator attached to the ring pull...