I’ve updated the licensing for the Cloud Clothes designs. I make them available “CC-BY” as per the wordle creator, Jonathan Feinberg. I let go of the GPL licensing because I’m told that wordle is “fair use” of copyrighted material. Furthermore GPL and CC-BY seem to me to have the same intent of preventing anyone downstream of claiming exclusive rights.
The designs are available for download from these two pages: Calculus and WP_Code_Cloud.  The shirts are once again available at www.cloudclothes.com

Downloads and sales of my Cloud Clothes designs are temporarily disabled due to a licensing snafu.

The images generated by wordle.net are covered under Creative Commons Attribution and require that derivative works be covered under the same license.

For my Cloud Clothes, I chose source text covered under GPL and require that derivative works be covered under the same license.

It may take some time to get the licensing and attribution sorted out and printed correctly on the shirts.   Apologies for any inconvenience.