Dexter Russel Hi-Carbon wide stiff boning knife, 137X series. I like the 1376 with the six inch blade the most versatile. You see the 1375 on most commercial boats, they don't fillet, they just gut the fish, so the shorter blade is preferred. I like the 1377 and 1378 for larger fish but can make due with a smaller blade. I put the tip of an 8" 1/3 of an inch into my palm one day when the weather got bad. The blood bubbled through the slit in the glove and I kept it on all afternoon. I didn't even look at my hand until we were on the way in 3 or 4 hours later...
If you prefer stainless the Sani-Safe series of boning knives is the same as the above with a plastic handle.