Someone recently asked me about Artlandia SymmetryShop, so I thought I'd talk a bit about my experiences with this product. It is advertised as a Photoshop plug-in, but when properly installed, it is accessed in Photohop via File>Automate>Artlandia SymmetryShop. That technicality aside, I think it's a fascinating tool with an extremely steep learning curve. Every time I use it I learn another factoid, but all is quickly forgotten if I don't use SymmetryShop every day. What does it do? It takes the material in your Photoshop file and arranges it according one of the basic symmetry types. It's very useful for creating repeat patterns, whether you are designing print fabrics, wallpaper, woven or knit jacquards, etc. (Its sister product, named SymmetryWorks, works with vector-based files rather than pixel-based files, and is to be used with Adobe Illustrator).
How do I use it? I've been producing repeat patterns for jacquard weaving, and to a limited extent dobby weaving. Since dobby lift plans are so small, I've found it best to do large, simple designs and then reduce them in size for dobby, instead of working initially on a small file.
The above image is one of my SymmetryShop designs in 4 colors for jacquard, and the following image is a loom-ready file derived from a similar design.