Comment by shabble

I think this occurs to nearly everyone. It's commonly referred to as a "pepper"[1], and is generally considered not all that helpful in most scenarios, as well as being potential evidence that you're a witch^W^WDoing Your Own Crypto, which is bad.

[1] See towards the end of the very comprehensive first answer. http://security.stackexchange.com/questions/211/how-to-secur...

Then go back, read the rest of it :)