I have been meaning to post a pic of one of my knives for a while here...
This is a NON-locking folder... But it is SO small and sharp and MUCH easier to safely handle that I really need to put one in my DR-PSK...
It is the A. G. Russell™ Ultimate Pen Knive...
It is TINY and SHARP(though the very TIP needed a bit of work to make it as sharp as the rest of the knife...
At 0.2oz you will not even notice it is in the kit...
Be sure and get one with the bail, as you will need to tie something to it after you take it out of your kit, because it is WAY to easy to lose...Yes it is THAT small...
I am afraid to carry one in my pocket, because when I empty my pockets, it is harder to find than a dime sometimes...