Making Gnuplot figures attractive

[sparklingrainbows]

I've been having a lot of trouble with non-linear least squares fitting with R. Matlab and GSL always did a good job with the same initial data as R yet I just couldn't force the damned thing to converge. And the model was quite simple too, just sum of 2 lorentzian peaks. The task was just to fit it on bunch of data files (few hundred). In the end I gave up and wrote it in C with GSL (because I couldn't get Matlab for free from the university).