title: Iterate SHA512 to make it more secure?
body: <p>I currently use SHA512 with per user random salt to hash user passwords and store them in a database. I thought this was pretty secure until I read this <a href="http://codahale.com/how-to-safely-store-a-password/" rel="noreferrer">article</a> about the use of cheap GPU's to brute force attack passwords. </p>
  
  <p>As an alternative to changing over to bcrypt would it improve security to simply use the SHA512 multiple times? Running it say 100 or 1000 times on its own output to slow down the process and make it that much harder to brute force? Or does iteration of SHA512 actually yield no security benefit?</p>