Question

What's your favorite cutting tool for fishing? What's your favorite metal for the cutting tool?

Answer 1

Cutco culinary sells a sports filet knife that has a gripper built into the sheath for grabbing fish tails when filleting.  You don't have to remove or expose the knife to use this feature.  There is also a notch that exposes a small section of the blade edge which allows you to cut line without removing the knife from the sheath.  On choppy seas not having to remove the entire knife helps keep everyone safe.  Second best thing about this knife is the handle hides six inches of the knife blade.  A small fastener on the handle when opened allows you to lengthen the blade by pulling out the hidden length and turns your six inch filet knife into a ten inch one.   First best thing about this knife is Cutco's unconditional warranty.  They have replaced two of my blades when I sharpened them down to next to nothing.  Their customer service is great.  Check them out.

Answer 2

Because I mainly surf fish and knifes get lost, I tend to use the cheap bait knifes.  They work well long enough for me to loose them.  For cutting line etc, I have a Gerber multi-tool that I really like