Finally! A crowdfunding project that will actually sharpen your number crunching skills using ancient math principles! Here is what RapidMath is: RapidMath cheatsheet is a compilation of techniques for rapid mental or paper based calculations involving addition, subtraction, multiplication, division, calculating percentages, finding squares and square roots and fractional arithmetic. The principles are based on ancient Vedic Mathematics (originated in India during 1500 BC). There are PDF's and poster sizes. Perks include the different sized posters. I am happy to see projects like this become successful.
You can get your poster here: http://www.kickstarter.com/projects/1373995643/rapidmath-educational-poster-for-rapid-mental-math