Random Prime Generator/Modular Arithmetic

[Tuvas]

Yep, you guessed correctly about the s2num function, I knew I should
have put a bit more.. It just converts an ascii string to a number,
however many numbers that are nessicary. I could indeed check for all
primes below a certain number, however, it still seems to run quite
fast, at least to a 400 digit number. It's not something I'm going to
use a ton, so optimizing it might not be worth it much more than it is.
Perhaps I'll try all primes at least up to 100, that wouldn't be too
bad... Maybe I'll have to modify my old prime string to output the
python command to check all of them, it's a bit of a pain the whole if
0 in (n%2, n%3) stuff, and I can't think of a better way to do it
without writing a new function to do so.
I'm going to post the new code in just a minute, it's running quite
nicely. I'm also posting my RSA function, which I believe should be
secure enough. I'm uploading the code to them now, the HTML page'll be
a few minutes...