It depends on where I'm at, where I'm going, and what I'm going to do.
As the director of the warbird recovery team for the Florida Aviation Historical Society (F.A.H.S.), if I'm going out in the swamps looking for a WW2 aircraft wreck that crashed in training, then I'm going to strap on my machete.
If I'm just shooting my CVA 50 cal mountain rifle at the range, I'll usually just strap on a small swiss army style knife or carry my butterfly knife in my back pocket, for cutting rags for barrel cleaning patches.
If I'm diving, I'll strap on my dive knife.
If I'm camping out I'll usually strap on my big swiss army style knife that has a full size fork and spoon on it along with all kinds of other things on it like scissors, corkscrew, screwdriver, knife, etc. (I mostly find I just use the knife, fork and spoon with that one when camping out). Along with that very usefull knife, when camping, I'll usually also strap on my western bowie or my survival bowie.
If I'm cleaning a batch of mullet or any kind of fish, I use my western bowie. It hacks their heads off really fast and even though its a big wide knife, it is so sharp it also filets the fish out real quick and nice too. Just cleaned a big batch of mullet with my cousin about a week ago and used it then. He was amazed how fast I could cut the heads off and filet them with a knife that big and wide. With its big handle and strong wide blade, you can cut those fish heads off real easy. Much easier to use it than a filet knife believe it or not. It also doubles as a cleaver and even as a small hatchet.
I would say my favorite knife is my Western Bowie that I've had for about 25 years.
Here's most of my knifes below. (I have a few more in my dive bag and one on my BCD that are not pictured).
1. Top, inexpensive $8.00 machete with nice grip rubberized handle from Harbor Freight. Gets the job done on brush.
From left to right...
2. stainless throwing knife.
3. An old black handled buck folder.
4. My big swiss army style everything knife with fork, spoon, knife and everything else in tan scabbard that I've had since a small boy.
5. Three small swiss army pocket knives.
6. A stainless folder (just below the three swiss army knives).
7. my butterfly knife which I have used a lot. Very handy.
8. To the right of my butterfly knife is my main dive knife. It's a lot like a marine k-bar. It's stainless but from use in salt water it has a few pits anyway.
9. My all time fav...my cherished full tang Western Bowie that I've had for around 25 years that holds an incredible edge. I have the top drop point section sharpened razor sharp too. Being carbon steel in the white it used to want to rust. So I steel wool'd it and blued it and keep petroleum jelly (vaseline) on the blade when I clean it and put it away. (I do that with all my knives to preserve them).
10. My double edge'd trench knife dagger with "brass knuckles".
11. My stainless survival bowie knife from Harbor Freight. It only costs $8.00 on sale and it isn't full tang because it can't be and still have a hollow handle which holds matches, fish hooks and line, razor blade, compass, safety pins, and anything else useful I can stuff in the handle. If I unscrew the top and take everything out, I can also jam a long stick in the hollow handle and make a spear out of it for spearing fish if necessary.
12. A neat mid size knife a friend gave me that I use for a variety of things like when I skinned out a hog a couple of months ago.
Closeup of my bigger belt knives.
Closeup of some of my smaller knives.
Closeups of my well used, reliable, razor sharp, full tang, cherished, Western Bowie. (My fav knife of all the ones I own).
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. A man can never have too many guns nor too many knives. 
