One billion (10^9) digits of pi (actually 1,000,000,001 digits if you count the initial "3") are in the file pi-billion.txt. The MD5 checksum is in pi-billion.md5.
JA0HXV has calculated 100 billion digits of pi and posted them at the website: http://ja0hxv.calico.jp/pai/estart.html
Kanada, et al. have calculated 1,241,100,000,000 (over 1 trillion digits of pi) in December 2002 but have not posted them: http://www.super-computing.org/pi_current.html