From Forensics Wiki
Rainbow tables are large pre-computed tables that make it fast to determine what word produced a particular hash. Rainbow tables only work if the following conditions are true:
- The hash algorithm was known when the rainbow table was created;
- No salt was used in the individual password.
Free Rainbow Tables
These rainbow tables are free for download.
Windows XP & Vista passwords (LM & NT hashes)
- http://www.renderlab.net/projects/WPA-tables/ (only for top 1000 SSID list)