Old users of GAMEBANANA remember this awesome kill icon pack. Unfortunately, when CS section was deleted, this pack has been forgotten, noone owned and could upload it. Today I've found this and I think it's worth of submission, because it's nice piece of work. :)
It works on all resolutions, but I suggest you to use at least 1024x768 (I'm using 1680x1050 and works perfect), because on lower resolutions icons will be big and may cover up the game screen.