If you're using Apache, put the file containing the password in a subdirectory, and add the following .htaccess file to that directory: 
Order deny,all
Deny from all

[download]
Voila! Nobody sees it.

The only risk you have is that if one day you munge the .htaccess, the directory will be visible. tadman's advice below is sounder in that regard.

In reply to Re: Best way to hide passwords. by dws
in thread Best way to hide passwords. by SilverB1rd

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