>>10831the problem is that, assuming the digits are random, on average it takes a number of length n to point to a message of length n. And, since pi is iterative, you'd be incurring gigantic computational cost as well.
Proof:
let your message be m1, m2, m3, ... mn
the probability that a series of random digits matches your message is 1/10 * 1/10 * 1/10 * ... = 1/10^n
therefore if we take a sample of all messages of length n in the random sequence, on average you would have to sample 10^n sequences to get a matching sequence. (10^n * 1/10^n = 1)
It just so happens that it takes n digits to represent 10^n in a base-10 system. This could not be compressed to base-exponent notation because in most cases the number would not be 10^n.
Therefore, on average there would be no compression performed.