As was noted, the amazing, 3,000+ installment XKCD story Time featured a synthetic language (with its own script) created by a linguist for the story. Deciphering Beanish is a blog where the language is being slowly, surely made legible.
This force-directed graph visually translates most of the relationships among Beanish glyphs. It was made with Graphviz, with a source .dot file generated by a Python script. I used the results of the Maximum-Likelihood classifiers I ran yesterday, from 2 to 8 groups, adding or subtracting a score (the value of the uniform distribution for that classifier, for example 0.25 for the one with four classes) from each glyph to glyph edge. Only positive edges are shown.
(Thanks, Tiago!)