A knife is a great tool to have while out on the road, camping or doing anything close to either. I'm assuming many people who bring one would prefer some type of a multi-tool, such as a [i:f0104ea2d9]Leatherman[/i:f0104ea2d9], Swiss Army Knife, etc., for multi-tools work great in many different tasks.
Some may think this is a bit overkill, but I bring three knives, and they all have their place:
[b:f0104ea2d9]1[/b:f0104ea2d9] A working knife. This one is a good, strong, high carbon steel fixed-blade knife which I use for a ton of jobs where a good, very sharp knife which keeps an edge should be used. Comes in hand, especially for carving. I consider it my main knife.
[b:f0104ea2d9]2[/b:f0104ea2d9] A fillet knife. Used basically for filleting fish or skinning small game. It's stainless steel and I use it because I don't want guts (and the steel corrosion that can come along with it) all over my work knife
[b:f0104ea2d9]3[/b:f0104ea2d9] A multi-tool. When I didn't carry a multi-tool, I came across many scenarios where I wished I had one. I now bring a swiss army multi-tool with pliers, a knife, a saw, a screwdriver attachment, and a hand-full of other miscellaneous parts. It's got a bit of heft to it, but it comes in hand and it's worth bringing.
If I plan on spending a lot of time in the wilderness during the trip, I also usually bring two main tools for harvesting firewood: a camp axe ([i:f0104ea2d9]GrÃ¤nsfors Bruks Scandinavian Forest Axe[/i:f0104ea2d9]) and a compact folding saw.
So the question is what knife, or knives, do you bring?
Edit: Removed a link that went bad.