A leatherman can perform a great emergency manicure!
I'm sure you can all guess the mental image conjured by this.
There's nothing to fall off the knife itself, for a start, and it's solidly built & sharp.
Frankly if con food's as bad as the stuff at Linux Expo was, you might need this anyway.
The PST II doesn't have a bottle opener; I have one of those on my keyring anyway.