So, what's the largest number you ever generated in a program? My record so far is 11650 digits. Ok it was just some uni homework I did because I was bored, but it still counts.
btw, my math library is super-slow - we had once a thread about computing factorials, and it did teach me that doing number computations fast is not as easy as it sounds.
[Edit:] the computation above took like 2.434 seconds. I guess a good numerical library would do it in the milliseconds microseconds range. However, my code doesn't use any external libraries, so I wouldn't change it for GMP or anything in the world :)