Hi,
I have been using the substitution technique for numbers since I was 11, but only the straight numbers like phone, credit card, social security, whatever - just digits, no exponents, no fractions, no decimals, no physical constants, and no greek letters. In aerodynamics loads of the exponents are capital R, capital M or whatever, where the letter could be anything from a constant to another equation, depending on what they defined in the preceding paragraph. So if there is a good system for memorising equations out there I'd love to find it. If not I might just roll up my sleeves and make one myself 
I will try the "flash cards" (up to the right is creating something new, up to the left is remembering archived information, btw) for remembering, just in case it works 
Thanks for the link to the O'Brian article - I've decided to order the "pass exams". What the heck! I'll probably learn lots of fun tricks as well as a couple of useful ones (though why I would ever need to memorise a full deck of cards remains a mystery to me!).
