I actually wanted to give a little more on this topic, but well, I am too lazy. So I just looked through my old files, and there I found an old piece of software, called "Super Pi" (googling for it I found a
propably newer version, but I did not download or test it). That was probably before the millennium (so quite some years ago), I still used Windows 98 SE, and I can remember letting my computer run a whole day for this, getting an
about 36 MB large file with digits of Pi.
In those days, I found that very interesting; meanwhile, I see that it is rather useless, but now it is interesting for the sweet sweet memories.