I am doing my very first secure erase using...Mac OS X Disk Utility!

I decided to do a secure erase of my new 160 GB portable drive. I had copied some of the Macbook hard drive to the new drive but instead figured I might loose this drive so it would be better for music as music is not my data and is in a sense public data by the time it gets to me. Not that I have downloaded illegal music but public in the sense of it not being private data about me or my life or relations or our finances. I might rethink this but for now I am doing a 35 pass zero write of the hard drive and this will take approximately 60 hours.