Mike, Thanks for the post - I've never gone so UL on a hunting or fishing trip, but it is helpful to know that an SAK Classic suffices.
Others: Mike's knife is an SAK Classic, but with an aftermarket, hi-vis orange plastic handle. I saw it in the R2R2R trip.
If I wash up on a distant beach (again) or get flushed down the river and need to feed myself, 1) I'm picking berries, edible plants and even bark before I chase down a Dall sheep or a black bear with a spear, and 2) I'm far more likely to land a fish, throw a rock at a ptarmigan or club a porcupine with a stick and have a gutting job more like Mike showed, than skinning out big game.
For actual big stuff, which I deal with a few times a year, I'm liking:
I got the version with the "black traction coating": 2.4 ounces in a very functional sheath and 1.3 ounces without. It is just as functional and vastly lighter as what most hunters carry with them.
I'm seeing more hunters use these replacement blades:
in knives designed for them. They get super-sharp blades instantly by popping in a new blade into the holder. But my UL and uber-cheap thought is that you could buy just the refill blades and use it like you would a razor blade, but as a whole lot more capable blade. There are several lengths of blades available from $0.80 to $3 each. If someone else would be interested in giving that a try, PM me with a snail mail address and I'll toss one in the mail. I don't have them in hand yet, but I'm guessing I'll belt-sand some finger grooves into the replacement blade and maybe paint a little plastic goo on the back side (the stuff you can dip tools into to form a handle around it).