I peanut butter one slice of bread and then wipe the excess peanut butter on the clean slice.

how have you never tried peanut butter? O_O;
I usually clean the knife off with my finger and eat whatever it was. :p Sometimes I'll lick the knife, but usually my sister needs it after me and I'm not mean.
When there's still a lot of peanut butter on the knife I scrape it back into the container. When there's only a small bit left (I smear only one half of my sandwich) I wipe it on the clean side.
Peanuts with butter? Preposterous! Peanut butter is mostly just...peanut. :x (not a huge fan either though)
I usually just scrape whatever it is back into it's container, or toss it in the sink.
I lick it.
Especially if it's Nutella on the knife :)
My mum still shouts at me to this day if I ever lick a knife, lmao. Thus, i've been trained to scrape the remains back into the jar. :x
I'd scrape the remains back into a jar.. or maybe lick it off if nobody was around and it was honey or something xD
scrape it back, but if it's full of crumbs then I just wash it off D: I hate to waste it but seriously don't want to lick it off. Ewww.
Okay, like ANTIpathy, if it was honey I'd lick it for sure. Butter, no thanks :x
THEY CAN'T BREAK YOU IF YOU DON'T HAVE A SPINE
It depends on what it is and if anyone else is going to use it. However, growing up in a family of 6, my first instinct is usually to scrape the rest onto the edge of the jar, whatever.
If it's something really tasty, I'll definately lick and not tell anyone.

Dirteh.
I hate peanut butter.
If it's butter, then I'll scrape it on to the side of the bread to avoid putting crumbs in the butter dish (butter crumbs drive me fucking mental). If it's something yummy that tastes good on it's own, like chocolate spread or jam, then I'll lick the knife. Peanut butter is nasty. And then I'll put the knife in the dishwasher.
I always lick it for sure!
Unless it's just regular butter. Then I put it back on the rim of the container.

I don't like eating peanut butter by itself. I wipe it on the edges of the bread. But I will lick most other stuff (jelly, butter, sour cream, etc xD)
I never really thought about it. ^_____^ I guess just smear it on the bread?