There are a few lathe operations (e.g., cutting off and knurling) where
I'd like to have cutting oil supplied more or less regularly to the cut
but I don't do enough of it to invest in a commercial rig-nor do I want
the mess.

So I soldered up this thing from plumbing parts found at OSH.  The 'cup'
at the top is a pipe-size reducer thingy (hey, I'm not a plumber) and
the valve is one of those used for drinking water lines to refrigerators.