I have been learning more than I anticipated I would about gnuplot lately. I've been making up figures for a professor's paper (for which I've been doing research this summer) and now that we're down to the near end, there seem to be a fair bit of specifics involved. I've also picked up some useful abbreviations:
|xrange, yrange||xr, yr|
|l, p, lp||lines, points, linespoints|
It's been especially useful to have found out how to make plots shell script style, a la:
set terminal postscript eps enhanced color
set output "something.eps"
set size square
set xr [-1:1]
plot exp(-x**2) ti "woo"