This project is loosely based on the famous world map by Ethan A. Merritt. Gnuplot can not only plot bars and lines, but also labels - just what we need for this project. I parsed a few place names and locations from Wikipedia or (for the larger maps) from OpenGeoDB, and plotted them in appropriate size to their location. Optionally, I color coded the labels similar to the color scheme of topological maps.
These are the Town Clouds I created so far.
This is the plot file for the Saarland map:
My input file looks roughly as follows:
Locations needed to be converted into ISO 8859-1 back when I did this, since Gnuplot did a poor job at UTF-8. This has probably been fixed since.