piX - A fun little application that is able to calculate PI up to many decimal points.
Version: 1.02PiX lets you calculate decimals of Pi. Just enter how much decimals you want and click on "Start" button.
Operating System: Mac OS X
As an example, calculating 100'000 decimals takes 16 seconds on a G4/733.
Calculating the same amount of decimals on a CoreDuo 2GHz takes 5 seconds!
This software doesn't claim to be the fastest in the world. The fact that it lets you access the user interface while it's calculating slows it down. It's still fast, since you can calculate 1 million decimals in less than 10 minutes on a MacBook 2GHz.
The use of piX is completely free of charge