#1
To start a thread on another controversial topic, what is/are your guys preferred way of caring and lubing the nut? As it stands I just use a pencil tip to work some graphite in there before restringing. Are there certain lubes I should look into and try out?
#2
I use pencil as well. Chapstick also works. If your nut slots are in good shape (wide enough for the string to freely pass, and smooth) you shouldn't need any lube at all.
#3
Crushed pencil graphite and 3-in-1 Oil mixed into a paste is the classic guitar nut lube, but it is messy to make and apply. The only commercial preparation that I know of which has a very good reputation is Big Bend's Nut Sauce:

http://www.bigbends.com/
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