Being a very mathematical person myself, the thought of geometry in any form of a design scheme makes my heart patter. But we must not abuse it.
A particular mathematical design I always seem to love is the coveted zigzag pattern. I partially believe it's because of the letter Z, but who knows? Anyway, using such a pattern is a great way to bring geometry into your space, as well as a multitude of colors. The actual Z shape could include multiple colors, and doesn't necessarily just have to be a single solid.
Zigzag Wall Treatment
Here are two examples of zigzag pillows:
photo from jonathan adler
photo from urban outfitters
Here are two examples of zigzag rugs:
photo from pottery barn
photo from urban outfitters
And the addition of any type of tasteful zigzag art is also a great way to bring punch to your space! This can be achieved through colorful block prints, or even a lovely abstract painting, or anything else that uses the zigzag flare!
Just make sure that you don't overdo it. Using too much zigzag in a single space will be too harsh on the eye, as well as way too busy for the space. Decide on what piece of your space you want to have that geometric spark, and stick with it. Think simple.
Happy Zigzagging!