The biggest MD5 crack database : http://www.cmd5.com/english.aspx .The database is approximately 4TB.

This website contains the largest database in the world. You can decrypt the following categories of passwords:
1) Digital passwords up to 11 digits
2) Passwords up to 8 lower alpha
3) 7 length mix alpha-numeric (lowercase only)
4) 6 length mix alpha-numeric
5) Other common-used passwords