To really expand your mind try some noncartesian porn.  Edwin Abbot Abbott has nothing on 'Girls on Girls in Tightly Closed Nonorientable Spaces'.

"Right-Hand Rule", by Randall Munroe, licensed under Creative Commons Attribution-NonCommercial 2.5 License

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To really expand your mind try some noncartesian porn. Edwin Abbot Abbott has nothing on 'Girls on Girls in Tightly Closed Nonorientable Spaces'.