Never, never ever give out your personal information if it's not necessary. One of the biggest consumer complaints, if not the biggest is identity theft. Guard personal information with your life folks.
If you've bought stuff at places like Best Buy or Walgreens — you might want to take a close look at your inboxes. Those companies — as well as TiVo — are warning that they have become the latest victims of hacker attacks that have given bad guys access to customers' files — including email addresses.