I don't carry a lot of fixed blades, but of the ones I do have it's obviously the Mora Companion. I forget it's there till my dog starts licking the BBQ grease dripping from it.
For a folder, it's a close call between two all SS knives: Delica and Leek. They don't grab my clothes or rub my skin, they heat up to body temp easily, and even though they're heavier than other handle choices they're small and thin enough to melt into my pants wherever they may be clipped. If I had to choose one I guess the Leek wins for being smaller and lighter, but they both work.