"The largest free database of p I could find on the web offered the first 400 million digits, in 40 separate documents. Out of curiosity, I used a program called PiFast Version 4.3 to calculate the first billion digits. This program can be download from the link below:
It took 17 hours, 53 minutes, and 38.14 seconds to calculate these digits on my Pentium 4 2.8GHz computer. The program can calculate up to about 20 billion digits before crashing, although this would take several weeks on a typical PC, and would require 400 separate files to decompress it."