用于密码哈希的非随机盐

UPDATE: I recently learned from this question that in the entire discussion below, I (and I am sure others did too) was a bit confusing: What I keep calling a rainbow table, is in fact called a hash table. Rainbow tables are more complex creatures, and are actually a variant of Hellman Hash Chains. Though I believe the answer is still the same (since it doesn't come down to cryptanalysis), some of the discussion might be a bit skewed. t